Today I was just going to run over what we're doing at Deakin in terms of this space of integrating storage with description discovery is where I've loosely described it. So I'll start the presentation if it's going to advance for me. So we've got a fairly loosely coupled ecosystem to handle this at Deakin which is great. It's flexible in design but as I've said there it causes a lot of confusion in practice and I've had a lot of problem getting researchers engaged with the fabric because it is quite confusing and you'll see with a diagram I'll present a couple slides later what I mean. So just trying to disambiguate some of that and clarify what the tools are about and how they can actually assist rather than inhibit publishing of data and using the storage is really what the focus is on at the moment. So in the described space we implemented Redbox Mint under the two in the commons and other ANDS funded initiatives and we call that research data footprints to describe the footprint of your research. We've got the discovery layer so that repository isn't what we present to the world at large. We feed that into our Azure Thunder Research Repository which is called DRO, Deakin Research Online and then that's what's Research Data Australia harvests for the individual records and the actual data that may be shared in an open way is made visible through a very simple very basic portal called the Deakin data portal which is basically just a Mopachi server on top of the data itself and I'll show a demo of all these things later on to expand those screenshots. So when we were implementing this metadata repository we also implemented a research data storage system which allows researchers to provision storage themselves. We didn't have any strict requirements on that so anybody can create a bucket to store data but it is aligned with that data portal when a research is ready to they can publish the data itself and it will link those things together and that's what allows it to be exposed to the data portal. So how does this all fit together? This is the diagram I was talking about just before so we've got various components and I'm sure most of you would be familiar with some of these systems in play but basically the management system is the source of truth for project and party data around researchers that feeds this repository I was just talking about. The storage system can be you can create storage and choose to link it to a project or not. So I'm absolutely with that because we understand that the actual process of writing a grant can actually generate a bit of data so before success outcome so we didn't want to dissuade people from using the central storage that we've got on offer and really it was also a character to stop people buying external hard drives and storing data locally on their machine so having that resilient storage in our data center was a pretty key point for that service. And then the rest of it is pretty familiar to most of you so we mint DIYs against every data set that's created and expose that through to this fabric down the bottom. So it is a bit of a quagmire and does cause a bit of confusion but with the presentation layer which is our focus on the moment it is limited in that it's just a bucket of data and we're just presenting it as a list and so the benefit to the researcher is limited and that's what our focus is on now is looking at well how can we better make people aware of this storage that is available and how it should be intended to be used and how can we better display some of the data that people are generating. At the moment I'm getting a lot of people creating storage containers or collections and just backing up their whole hard drive to it and there's really no description and delineation to how they're describing things so it's really identified to me that there's pretty poor practice out there in terms of how people structure what they're doing and so that's where our library staff are helping out a lot in that one-to-one or one-to-small group discussions around how better to describe and manage data in the broader context. What I was also going to say there is we've got a portal at Deakin called Deakin Sync and we're looking to provide some context to what researchers are doing there around storage and so when one of the ideas is to link present to the researcher if they've got a successful grant outcome present to them the option of creating storage if we know they haven't linked it to that project already because we've got all that metadata there we can actually leverage quite a lot so with that portal we can provide a lot of value and direct all the researchers to go there to say okay well you may want to be creating some records because we can see the project's been running and it's near the end of its life cycle or at the earlier stages we actually create storage to put the data in that you're planning to generate with that project. The other options in the presentation layer we're looking at are discipline specific or quite aggregated systems that allow you to display data for various different disciplines so we're only just starting to look at how we can integrate these things into this platform or this ecosystem and so those things are like a meeker for all different disciplines that may want to create collections and manage them themselves and use that as their presentation layer rather than just a bucket with a patchy index on top of that. FigShare and Mitardus are bringing around image data, FigShare being quite general and looking at FigShare for institutions and how that could potentially play a part or MediaFox were still really investigating all those different options. So that's the real ecosystem and I didn't want to go into too much on that and really wanted to show you how it all sort of functions. This is the red box system we have and most people would have seen that in the past. It's allowing you to create the data descriptions as we all are well aware. What I wanted to show you here was the process we go through for each of these and how the DOIs are linked into the actual the data portal side of things. So when the process is they create a metadata record and then when they're ready to publish the data they click a publish in the store which I'll show you in a minute and then the links for that come into here and it publishes this data portal link and you may be able to see on the screen the URL down the bottom which keeps those two things in check and then when you go to view that actual data collection you can then see it on this data portal and which one was that? The interview data for some Papua New Guinea audio interviews. So we replicate the metadata from that footprints record and actually show the contents here to be able to download if you want to. But it's very very basic. There's no packaging of that which would be really ideal. There's no thumbnail sort of view of that so really you're just downloading in that first example there 800 megabytes and then you can actually understand what it's all about. So exporting the metadata of that mpeg file in this case is not really done at this point and that's where I'm wanting to get some improvements to present that better. The data store is this system here it's just a web application that hooks into our corporate storage that we have available and what we've done is provided four collection types and we allow researchers to create those activities they can link those to a project and then they can create these buckets to store things so they can create a traditional network attached file share which is these little yellow icons and they can create any number of those. There's a nominal limit of 10 but they can create any and they are unlimited they can put as much data in there as they like and that uses our what technology we're using now we're using Isilon storage for that so it means this snapshot's taken three times a day one snapshot at the end of the day for three months so they've got complete ability to restore files and manage their data very flexibly. There is another one called a publishable file share so when they're ready to publish data they can create one of those it's no different in terms of the technology but it allows you to hook into the actual footprint's record and then that little data portal link happens. The other one there with little star this is an icon for a product called Syncplicity so we're providing a Dropbox-like service because we needed a lot of researchers working with external parties and they've got a lot of issues sharing data externally so they can use this service now to do provide that so that's using our own on-premise storage with a Sync and Share platform on top of that so it gives them unlimited storage although unlimited in since that you need the storage on your local computer for that to really function but it has been very it's taken up quite rapidly because people really want that capability without having to pay for a Dropbox account and use that storage and the other collection which I don't have in this demonstration activity here is a wiki space so we've got a Confluence wiki instance which they can use to collaborative work internally and so the store the rest of the store has really gone from storage as in storing data to actually a store as you buy things and so that's going to expand we'll be providing a whole lot of other services through this research other store so blog engines and omicron instances and a whole lot of different things will be provided through this one portal for researchers and it all be tied together under this this activity or this project banner so a particular example I was going to show you is the is a Pacific Sea Star but Mark he's got a some sequence data that he's produced and he wanted to make it open so he's gone ahead and published that he's credit the now Fez Fidora Asher repository record through our footprint system and then he wanted to share that to the world so originally he he was working with the library and they stored the objects within the repository which wasn't great and so now they're provided through the data portal and so you can download the gigabytes or megabytes in this case of files and one thing I'm advising researchers is to really be descriptive about what that is I'm sure people in his discipline understand what all those different file formats are but it doesn't really have a overview sort of read me file it could describe it better so we're working with them on that and that's presented with that hook up through that that link there and also is I think that's available here so you can actually be taken straight to that record all the DOIs map through to our research repository so footprints really is just a collection gateway that links those things together and allows the the record to be curated as accurately as possible so really that's all I was wanting to cover off today can Chris talk more about the publishing function absolutely so really it's it's we call it published but it's it really disformalizes the link between the two systems they create a publishable file share which is just a a network attached storage location everyone should be fairly familiar with network touch storage this is a network drive and so they would just have a folder like this to store things let's just say this workshops one for example is something though it's all that would structure their data within that space that's completely offline it's not exposed for anyone other than themselves and then when they're ready to publish the data I'll just see if some of the this is uat so the I might get some errors but when they're ready to publish the data they can then click a publish button quite simply here's good it's ready to go so this particular folder which is fictitious because it's uat but when they're ready to publish they literally do that it will then look at the all the effort prints records and provide a list of ones that they that haven't been published and they can just choose that so in this example here I've already published against this other one but this one here I could potentially do that and then I can provide global access so to say yep anyone can get access or I could restrict it to an af member so in some way you could limit down to anyone who's a member of the af to who could see that so that's sort of semi open in terms of this collection and then within a few minutes that collection would be exposed through that data portal I showed you before so you would see it would appear here or if I logged in and it was restricted there would be more exposed once I'm logged into the system so anyone in Australia can log into this this data portal as you can see and then see that so that's how that that's that's working all right Chris there's a whole bunch of other questions that are coming in as you do that and says what's the maximum storage space the research you can request is there a maximum did you say yes what is the maximum none it's unlimited well I'm sure they'll all like that one so our IT managing the growth and capital acquisition that has to happen and they deal with that as it goes so yes it's completely unlimited so this next question probably ties into that which says what's the cost of the implementation what do you have a data storage costs so there's no explicit cost it's covered under our central capital expenditure on storage so it's just factored into all the storage that the university buys so there hasn't been an explicit cost for this particular service at the moment there's just about what are we up to 100 terabytes with another 60 at another site so nearly 200 terabytes is what we're looking at so not overly large we don't have any astrophysicists with a petabyte in their back pocket so it's it's probably relatively small to most institutions but it is it's covered under that so they provision that under systematic procurement throughout the year so every time that they're always negotiating a new price for that storage so I don't have to worry about that which is actually a luxury risk position to be in so probably that ties into that is a couple of questions which sort of meld together one is says use of storage by external to deepen users most collaborations in our national or international so is this possible that the external to deepen users can use it and there's another question very similar which says is this service going to be available for researchers in other universities and is their storage size limitations so the first bit is covered under that sync and share service where they can they can provision it so a deacon identity can provision it and share that with colleagues they're working with other institutions which but there are limits to that because if you're synchronizing to your own computer you need the hard drive storage on your own computer so there are limits the traditional network attached storage any deacon identity can access that because they can create a VPN connection but the external people can't so the way that's traditionally being handled at deacon is we often make those collaborators we need it as a visitor to the university and then they get access to the to the storage that's a little bit cumbersome and I don't but most people know how to work around that and then follow that process and the last question no there wouldn't be the ability for non-deacon people to create the storage space in the first place it really has to be instigated from deacons perspective okay another one is are the researchers able to mint DOIs by this publishing method yeah so in the footprint system that's where the DOI is minted and they are done by the library so the library when they're performing quality checks on the description are performing the step of minting it so it's done implicitly in that the workflow of a metadata record is curated by the library and they're the ones actually doing that but it's effectively it's a business to business transaction that happens on every one of those records so yeah the research themselves don't but the library does it on their behalf okay and then probably the last one so we can keep to Paul's time he says is that all the data stored on deacon infrastructure or is it stored on national infrastructure either this or local e-research provider so yes it is all on deacon infrastructure so amongst our four main campuses we've got two data centers and it's stored on the data within those data centers and replicated on those two so we haven't engaged with the the RDSI provision storage it's all purely within on-premise which our research is like because it means they can particularly if it's sensitive data they can tick a lot of boxes in terms of their compliance that they need to ensure


Family Theatre presents Anne Blythe and Sterling Holloway. That work in cooperation with Family Theatre Incorporated brings you Anne Blythe and Sterling Holloway in George Lathrop's comedy In Each Other Shoots. To introduce the story, your hostess, Anne Blythe. Thank you, Gene Baker. George Parsons Lathrop was the son-in-law of Nathan Hawthorne. To a lesser writer, this might have meant remaining in the shadow of one of the great masters of American literature. But this was not true of George Lathrop. Poet, novelist, biographer, he was well able to stand upon his own literary feat. And his short stories had a quality of imagination and fantastic conception that caused them to live and breathe today, both as wonderful examples of the moors of human behavior and as true comedy. We invite you then to listen to George Parsons Lathrop's rollicking short story In Each Other's Shoes and to our star, Sterling Holloway, who plays the role of its most human hero, John Cromby. It all seems like a dream. Only six months ago, I, John Cromby, came to the great city of New York to seek my fortune. And today, a mere half year later, I own the entire metropolis, lock, stock, and barrel. The destinies of its three million people are held in the palm of my hand. Yes, it all seems like a dream. I reside at the lawn, that's the city's most fashionable and expensive apartment building, where a regiment of servants snaps to attention to serve my needs. While my valet tends to my clothes. Mr.  Blatchford, this suit, haven't I seen something like it before? Wait a second, Mr. Cromby, sir, I do believe that you wore it once, but that was over a year ago, sir. Blatchford, you know very well that I wear a suit only once. Sometimes not that often. Burn it. Well, yes, sir, Mr. Cromby, sir. Where is my wallet? The armored car is taking it to your office, sir. And my pocket change? Here, sir. I have your pin money right here. Once a month, I visit my offices in Wall Street to decide the financial state of the world. I'm admiring throngs follow every foot of the road. And the same annoying thing always occurs as I reach my modest 200-story office building.   I ask no more, even though my love for you is beyond words to describe. Just a glance, a mere touch of your hand. Please, Mr. Cromby. Poor girl. Like millions of others, you cannot resist my manly charm. No, no, no, my child, I shall not glance at you, not touch your head. Your life is unhappy enough as it is. Why make your future unbearable? Blanche could remove her from my path. Oh, yes, sir. Well, Blanche's father, J. Latimer Nittomer, once one of Wall Street's greatest tycoons, was now only my office boy. Oh, welcome, Mr. Cromby. Welcome, your office is all ready to receive you. Thank you. Has it been dusted as I ordered, Nittomer? Oh, indeed it has, Mr. Cromby, with genuine gold dust. Very well, Latimer Nittomer. You may unroll the red velvet carpet, and I shall enter. I... What's that? That, Mr. Cromby. That is the alarm system on your vault. The alarm on my vault? Yes, Cromby, you've been robbed. Your wealth is gone. You're now a popper, sir, a veritable popper. Ha, ha, ha, ha.  Yes, but it is, Cromby. Blanche, please. Hey, you are now a broken, penniless man. No, no, it can't be, really.  Blanche.  Blanche. Remove him from my path, Father. Out of the way, scum. Yes, we'll ride him out of town on a reel. Yes. No, no, please. Let go of him. Take him away, the common lowdown poppeljerry. Penniless poppery scum.  You hear? My slave. You can't. This is some horrible dream.  Here, Mr. Blancheford. Cromby, I have been calling the stock room for five minutes now. You have, Mr. Blancheford? No. What, Mr. Blancheford? Nobody answered, Cromby. Oh, they didn't? No, Cromby.  You will be fired. Yes, but, but.  Thank you, Mr. Blancheford. Now guess even here, with two dozen paper clips, and a ream of note paper, and rice away. And the next time I catch you dreaming on the job, I'll skin you alive. Yes, Mr. Blancheford. Foe on you. Here, what was that, Cromby? Yes, Mr. Blancheford, right away, sir. No wonder my conquest of New York all seemed like a dream. It was a dream. And as for Blanche Littermer, well, we both lived in the law and the partner building. She and her father in the 20 room sweetened me in a remodeled tool room they let me have for sweeping out the basement every Sunday. Then one day, as romance would have it, we found ourselves in the same elevator together. I only brought all my courage to bear, and I spoke to her. I... Hello. Hello, Mr. Littermer. Oh, hello there. You remember me, of course, Mr. Littermer. Oh, why, of course. Of course I do. How could I forget? They never came back, you know. Oh, they didn't? No, they'll always be terribly indebted to you for that. Oh, it was nothing. Was it? Your floor, Mr. Littermer. Thank you. Yes, we'll always be grateful to you. Fido and I. Fido? And the next time he's afflicted with fleas, I'll certainly buy more powder from you. Bye now. Yeah, goodbye, Fido. I mean, goodbye, Mr. Littermer. And then came the fateful day. And the day I'm going to tell you about. You see, I woke up kind of late that morning. It was raining very heavily, and I knew I'd have to hurry to get to work in time. I hastily grabbed my shoes from the hallway where I'd left them the night before for the porter to shine. I dressed in a flash, rushed to the office, and to my horror, I arrived one and a half minutes late. And no sooner had I reached my desk in the stock room. Hello? Yes, Mr. Blatcher, at once. It says that you are one minute and 33 seconds late. You see, I... That amounts to eight minutes and 38 seconds a week. Yes, sir, will you say... Or seven hours, 12 and a third seconds a year. What do you have to say to that crowned man? What do you have to say? Could I say, I stood there, looked down at my shoes and wriggled my toes. There was something funny about them. They were dry. Oh, that was very peculiar because my shoes had a hole the size of a half-dollar in each sole, and what with the rain outside, my feet should have been sopping wet. I wriggled my toes again. They were still dry. Then I realized what had happened. The porter had left somebody else's shoes at my door by mistake, and in my hurry, I hadn't noticed it. I was now standing before Blatchford in somebody else's shoes. I'm waiting for an answer. What do you have to say? What else could I do? I answered him.  What was that? You said...  You know Blatchford. I'm tired of being your slave in that stock room. I think I'll become a director of this company. As a director of this company? Yes, yes, Blatchford. Most of the board of directors will be held next week. I think I'll run for chairman. You can't be...  All right, fire me. And when I become chairman of the board, I'll fire you. Get out of my office.  Fui on you. Blatchford, good day, sir. I strolled casually, magnificently out of his office, chuckling delightedly to myself as I recall the entire conversation. And I got to the part about where he thought he had fired me. I fainted. I know I should have been morose and depressed, but somehow unbounded courage seemed to rise through me from the soles of those strange shoes I was wearing. Somebody else's shoes. And those shoes, well, they walked me right into a large office at the far end of the corridor. And they kept going and going to an imposing-looking door in the rear. I opened it and the shoes stepped right inside. And as the door started to close behind me, I caught a glimpse of the lettering on it. J. Lattimer, Littimer. Private. Well, what's the meaning of this confounded impudence, young man? Oh, relax, Littimer, relax. You and I have business to talk about. Oh, well, that's different. What do you mean? I don't discuss business with any unknown young squirter who walks unannounced into my office? Then I'll introduce myself, sir. I am John Cromby, sir, your new business partner, sir. You are? Really? Yes, sir. Well, I'm glad to know you then come. No, you listen to me, you. No, you listen to me, Littimer. I came in here to discuss a little deal. Well, it can net us a couple of million dollars, but if you're going to fly into temper tantrums about it, did you say... Gesundheit. Thank you. Did you say a couple of million dollars? I did. Net? After taxes. But if you're not interested, of course... Not interested?   Have a cigar. Have two. After all, what are a few cigars between old business partners, eh? I hadn't been fibbing to Littimer because, you see, from a physician of vantage in Blatchford's firm in the washroom one day, I overheard him boasting about an undisclosed surplus of some three million dollars in the firm's treasury. And to my utter amazement, I suddenly found I had a plan whereby Littimer and I could corner the market and the bountiful harvest of dollars would go to us, you see. And in return for my contribution, I asked only the modest sum of 50% of the profits and the chairmanship of the Board of Directors. Well, I finished my magnificent presentation, relaxed in my chair, and with an impressive flourish, I placed the end of my cigar in my mouth. You! Wrong end. Several gallons of water later. Littimer gave me his answer. My boy, my dear, dear boy, this will be a coup worthy of the greatest, the greatest, the... Gazuntite. Thank you. Worthy of the greatest financial geniuses of all time. Very well, and suppose you get started at once, Littimer. Did I shall, John, I'll... I'll... I'll... Gazuntite. Thank you, thank you. But I'd certainly like to get my hands on that, that didiotic, moronic imbecile first. Yes? Who is that, Littimer?  Traded shoes? Yes, someone switched shoes in the hallway last night without noticing it, I put these on. Did I call them shoes? Would you believe it? There's a hole the size of a half-dollar in each of the soles. There is? Yes, yes, so my feet got soaked in the rain this morning. That's why I have this... have this blasted coat. Believe me, I'd say that anyone responsible for such a dastardly trick should be drawn and quartered. But the very least boiled in oil. What would you say, John? Say, Mr. Littimer, I guess I'd just say, there's no time. Suddenly, everything had become horribly clear. My strange confidence and grasp of high finance. Mr. Littimer's submission to my forceful personality for due to a quarter's error, for Littimer and I were literally standing in each other's shoes. Well, I left his office and hurried to the nearest shoe store to buy a new pair of shoes for myself, and then I rushed over to his apartment to return his shoes before he learned of my involvement in the horrible mix-up. Hello there. Oh, hello, Mr. Littimer.  You are? Yes, I have a great deal to apologize to you for. Please, come in. Well, I, uh... Thank you. I don't know how you'll ever forgive me for confusing you with a flea powder salesman. Oh, oh, then you know that... Of course! I should have known all along you were the termite man. Well, I soon learned that Blanche Littimer was as intelligent as she was very beautiful. It only took me an hour to establish my true identity, and at the end of another hour, you were sitting on a Davenport holding hands. And as I told her of the mix-up of the shoes, oh, gee, we were enjoying the story no end when the front door opened. Well, John, John, my dear boy, I didn't expect to see you here. And I didn't expect to see you so soon either, Mr. Littimer. Well, it was, uh... It was, uh, this... Hey! It goes on tight. Thank you. It was this confounded cold. I thought I'd better come home early. But tell me, my dear boy, what are you doing here? Oh, John dropped by to return your shoes, Daddy. He did. Well, now that was awfully thoughtful of you, John. If you only knew how I suffered in these moth-eating 10-cent paper-sold atrocities all day, you'd... you'd... But, well, Daddy, your face is turning the color of the... My shoes, um... The penniless nincompoopies didn't wear the jackass who couldn't afford a pair of shoes with soles on them had the audacity to ding-dang rescue and gentle feathered nerve to bamboozle me into thinking you was a financier. Crumbly. Crumbly, get out of here. Get out of here before I... Well, and good riddance to rubbish, Blanche. If you ever let that... that four-flushing jungle and hide in this apartment again, I'll... I'll... I'll... I'll... Well, thank you, John, my boy.  I wandered out into the park, realizing it lasted I. John Crumbly was a perpetual failure, doomed to remain a stockroom clerk and a bachelor for the remainder of my days. There was nothing for me to do but return to Mr. Blachford on my hands and knees and beg his forgiveness. You'll do absolutely nothing of the kind. Hey, Blanche... Why, it's ridiculous to think that a pair of... of shoes could alter a person's personality.  But, Blanche, I don't feel like one. I feel just like a... a... a... a popple-jerry. Oh, nonsense. You're a sweet, wonderful, kind, marvelous young man, so there. Blanche... You... you mean that to me? Of course I do. What else could you be but sweet, wonderful, kind and marvelous when you're gonna make two million dollars for my father? I left Blanche standing there in the park. I walked back to Mr. Littimer's apartment. Listen, Mr. Littimer...  Oh, 23 skidoo. What did you say?  You're going to listen to me now. I'm going to listen to you. And just why should I listen to you? I'll tell you why, because I'm a sweet, wonderful, kind, marvelous young man. That's why. Oh, well, that's different. Blanche! And I'm going to make you two million dollars, whether I'm a mere stockroom clerk or a billionaire. Are you going to listen? Keep talking, son. Keep talking. Well, Mr. Littimer listened, and I talked to the results. The next week at the election meeting of the board of directors of Mr. Blatchford's firm... And I have here in proxies and voting stock certificates. 1,200 votes. And I cast them for myself. Theobald Z. Blatchford. As chairman of the board. Here, here. Blatchford's for chairman. And I, gentlemen, I have in voting certificates alone 12,000 votes. And as chairman of the board, I elect none other than myself. John Cromby. Yeah, yeah. Cromby for chairman. Fooey on Blatchford. So you have heard my story. It all seems like a dream. Only six very short months ago, I, John Cromby, came to New York to seek my fortune. And today, today I'm chairman of the board of one of the city's greatest corporations. And, well, as for Blatch and me, we had a perfectly wonderful honeymoon traveling around the world. Twice. Then we returned home and examined our wedding presents.  Oh, John, look. It's daddy's present to us. Isn't it unbelievably sweet of him? Why, sure. I should say so much. Can you imagine your daddy giving us a pair of solid gold shoes? And complete in every detail, John. Look, they even have holes in the bottoms of them. Yeah. Oh, here's a card that came with him, Blanche. Wait, wait, wait a minute. I'll see what he had to say on it. Blanche, I believe me. I never heard of anything so sweet and sentimental and poetic in all my life. Well, what is it, John? What did daddy write on the card? Just one simple, all-embracing word, Blanche. Because it's on tight. This is Anne Blythe again. You know, there are a lot of unusual things about family theater, but here's something that really makes it different.  And family theater is successful if it helps you realize that the family that prays together stays together.  From Hollywood, family theater has brought you in each other's shoes, starring Sterling Holloway with Anne Blythe as your hostess. Others in our cast were Barbara Eiler, Ken Christie, Howard McNear, and Jim Nussin. This adaptation of George Lathrop's comedy was written by Sidney Marshall with music composed and conducted by Harry Zimmerman and was directed for family theater by Jaime Del Valle. Our family theater broadcasts are made possible by the thousands of you who felt the need for this type of program, by the mutual network which has responded to this need and by the hundreds of stars of stage, screen and radio who have so unselfishly given of their time and talent to appear on our family theater stage. This is Gene Baker inviting you to be with us next week at this time when your family theater will bring you Barbara Britton, Arthur Shields, and Dan O'Hurley in King O'Toole and Saint Kevin. Join us, won't you? Family theater is heard in Canada through the facilities of the Canadian Broadcasting Corporation and is broadcast to our troops overseas by the Armed Forces Radio Service. This is the world's largest network, the Mutual Broadcasting System.


So, this is lecture 38, ok. So, there were a couple of classes which were not recorded before this, those of you who did not show up for those two classes you would not have a recording of that, ok. So, I think two or three classes maybe I did not record, it was basically to show demos of very simple PAM simulation, ok. Well, maybe very simple maybe not so simple, ok. So, to show LMS and the fractionally spaced equalizers and all the properties to show them in a simulation. Once again I had urge you to go and try to recreate that simulation yourself with whatever software that is applicable to you and people are doing the lab maybe do not need to do that at all, ok. Alright. So, today's lecture is going to be briefly on career and timing synchronization, ok. I will not spend, in fact I will spend very, very little time on this, just one lecture overview and maybe even just half a lecture because I want to return your answer sheets as well. So, very brief lecture is going through high level ideas, ok. So, what is carrier synchronization? You want to get back the frequency and phase of the carrier that was used at the transmitter, ok. So, you might have a nominal idea of what that is or you might be able to nominally reproduce that frequency at the receiver, but it might drift, it might change with time, it might change with temperature. So, many things slightly differ. So, you definitely need to be very accurate about your estimate of the frequency, that is one thing. The other thing is the phase is something which is which needs to be estimated and needs to be locked on to. So, it is called the lock. So, you lock on to the frequency and phase of the actual center frequency of the carrier that is coming in, ok. So, that is the carrier synchronization, ok. And I showed you some effects of what happens if the carrier is not synchronized in the simulations. You saw the constellation rotating all over the place and all kinds of errors will be introduced, it is not possible to decode. Timing is after the carrier means after you have done the down conversion, after you do a match filter or some filter you have to sample, ok. So, you have to sample at the sometimes at the symbol rate, sometimes twice the symbol rate, ok. So, if you tell us if you sample twice the symbol rate maybe timing is not that serious a problem, but still you have to be worried about it, but the symbol rate sampling finally you have to worry about. If there is a drift in the phase then there is a problem, in the timing phase there is a problem. What do I mean by a timing phase, right? So, in PAM serial PAM transmission each symbol is going to roughly correspond to one symbol period which is 0 to t, ok. Within that 0 to t you have to sample somewhere, somewhere in that point and that point might is actually unknown to you. You do not know you know at the transmitter what that point is at the receiver you do not know what that point is and you have to keep changing that to get a better and better estimate of where that point is and depending on your for instance if you are doing Ray's cosine pulses depending on your excess bandwidth this thing can be very crucial or not so crucial, ok. But still if the channel is bad and all that this timing can cause serious problems, ok. So, you have to particularly at low SNR it will cause problems, ok. So, all so the problem I hope is clear to you and in today's modern several modern communication systems like wireless systems and several other things usually people go for a very easy solution. The easy solution is to do what, ok. Transmit the carrier and timing separately using some dedicated bandwidth, ok. So, that is the easiest solution, ok. So, I am going to put that down as the easiest solution, ok. So, use something called control or pilot channels for transmitting for transmitting the carrier and timing, ok. So, the timing and carrier is usually derived from this control channels information usually in wireless systems this is very common and the reason why some some approach like this is taken is one can also argue that in wireless systems you mostly go for what are called packetized transmissions, ok. Short bursts of packets and each transmission happens in a short burst and after that you discontinue for a while and then maybe one more burst, ok. In such situations each burst needs to have its own training data, its own framing and all that. So, it does not make sense to expect something like a continuous timing that needs to be maintained that situation does not really arise, ok. So, in packetized communications some solution like this is much more preferred, ok. So, you have bursts of transmission and that is better, ok. But of course, there are other situations where you have to send long streams of bits without any pause for a long time and expect your carrier and timing to be in sync over a long period of time. Can you think of any examples of such systems? Maybe satellite is one example, what else? Satellite no one can argue there is lots of bandwidth, maybe power is not there, but it is bandwidth available. So, usually what happens is if you think of systems like I do not know maybe on the chip. So, inside a chip sometimes you need to send bits from one place to another place. Inside a board you may need to send bits from one place to another place and those situations you are really sending bits continuously at a fast pace and you do not want to keep packetizing it, you do not want to keep putting framing this and that and you do not expect too much timing. In those situations these kind of things make sense. When you have to send a long stream of bits continuously at a fast rate and you do not want to keep stopping and pausing and doing all of this. So, that is where many of these carrier and timing synchronization ideas are very, very popular. Maybe Ethernet for little bit people use these things. But in wireless systems and all these modern systems people use very simple methods to track minor drifts in the timing assuming the control and pilot channels are available to fix the major issues. So, that is the idea. So, what we will do in this course is basically see an assortment of techniques, no logical flow to what I am doing first and what I am doing last. I will just provide a few techniques, few things that you might hear, but it is not neither complete nor it is intended to be incomplete. So, we just for you to know these terms is to hear these terms once and not hopefully forget about it and remember the central ideas maybe one or two ideas here and there. So, one component which will show up all the time when you do, when you want to synchronize face, timing phase or carrier phase or whatever is what the face lock loop. So, the face lock loop I want to briefly mention should know it is a highly non-linear device very difficult to analyze with your traditional linear type analysis, but of course only analysis we do is linear. So, you of course do a linear approximation analyze. I am not going to talk about the analysis at all. I will simply provide a block diagram and give you a brief description of what it is supposed to do.  Maybe not the bit extruded. So, what happens is you are expecting a sinusoid as an input. So, you think of it as say let us say a sin I do not know some omega c t plus theta. So, this is what is the signal that is I am drawing continuous time it can even be discrete time. So, sampled versions also. And locally you have a certain version of this. So, I am going to call it sin omega l t plus theta l. This is your local version of what that is. So, first thing you have to assume is you can produce several such local versions. For instance is omega l can vary over a certain interval you should be able to do that. If you cannot do that then you cannot adjust it and then nowhere you can catch the drift and all that. So, there should be a device which lets you do that what is the device called. So, it is a voltage controlled oscillator. So, you need a voltage controlled oscillator whose frequency can be set by changing its input voltage and its output while being also used to correct the error is the actual carrier that you want. So, this is your output. So, what you do here is calculate error. So, it is like any other loop you always calculate error and feed it in. It is the same old thing all over again feedback loops. So, what is the error that you are interested in here? The error in the phase. So, what you have here is what is called a phase detector. There are several ways of implementing it. So, significant research I believe is still being done on improving on these phase detectors, improving on different components here. So, what is a phase detector do roughly its output should be omega c t plus theta minus omega l t plus theta l. So, this is what you roughly expect the output to be maybe there are better ways of defining that, but the difference between the phase of the two sinusoids that are at the input of the phase detector. Of course, there is a modular 2 pi. So, you do not expect it to keep on producing some continuous range. So, modular 2 pi. If there is a mismatch in omega c and omega l, then how will this phase difference look? It will be a triangular thing a linear thing with time it will keep going up and down modular 2 pi. What about if omega c equals omega l and theta is not equal to theta l, it is going to be a DC. So, that is what you expect that is what the signal will be. Other than that it is difficult to analyze this block why? It is highly non-linear, it is doing something very weird, it is doing a sine inverse and subtracted. So, it is not it is not easy to analyze this with Laplace transform or Fourier transform or anything like we cannot do any such thing. But you hope that it is close enough to being linear and then you analyze. So, people analyze it we will not do any such analysis. But this input by itself might be too raw to feed into the VCO. So, you do not want to feed this input to the VCO of various reasons too raw. So, usually you put a filter inside it is called a loop filter. Then the output goes to the VCO which is the voltage which will control the omega l change in the omega l. Of course, theta also there are some details involved here. So, one thing you can notice is one stable point of operation for this loop is what? When both are equal, when both are face locked, when both are face locked it is a stable point. So, in this system that is a stable point there is no doubt about that. And you assume around that stable point disturbances are linear and you analyze it and you get some important parameters. One thing will be what is called the I think the acquisition range it is called something.  So, there is two different ranges of frequencies for different PLLs all these things are designs. So, that is all I am not going to go into any more detail. It is also possible to design this in digital. So, today people even do digital PLLs. So, you can do the whole thing in digital. Digital in the sense this will be a sample sinusoid, you will be producing samples of sinusoids. Then the face detection and all one can imagine implementing highly non-linear face detector. So, it is what is the big deal it is just digital. You take sign, you take cost it does not matter. So, processor sitting inside it can read from a table if necessary. So, all these things can be done easily in digital and these things are implemented implementable digital also. So, there are blocks available which can lock on to a unknown frequency and face given a nominal frequency close enough to it. You cannot lock if you have only 10 kilohertz you cannot lock to 100 kilohertz frequency happily. You might have to do some things there are ways to get around that also. So, all these things are possible today. So, that is my brief talk about PLLs and I will not talk about PLLs from now on mostly. So, maybe one here or there I will mention, but mostly we will not talk about PLLs again, but this is a block which will show up again and again in these synchronization systems. So, the first thing we will see in PAM systems is timing synchronization, timing recovery by what are called spectral line methods spectral line methods. So, the methods that we will see mostly will be not decision directed at all. So, usually in the previous blocks I drew decision directed timing recovery you remember the one of the practical PAM receivers I drew had decision directed timing recovery decision directed carrier synchronization. What I am going to describe mostly today is something that is not decision directed. So, you deal directly with the signal somehow manipulated and derive your timing and carrier that is what I am going to talk about mostly. So, basically spectral line is so, the idea is briefly to exploit some kind of periodicity that is probably already available in your PAM signal. So, after all your PAM signal kind of repeats every t time units. It repeats only thing that changes is what the multiplying factor. So, definitely your PAM signal has some kind of periodicity involved in it. So, can you exploit that to extract a tone at 1 by t is the question. So, once you extract a tone at 1 by t you can produce your clock at the receiver. So, that is the brief idea behind spectral line methods. So, let us look at a baseband PAM signal. So, baseband PAM signal looks roughly like so, if you think of the receive signal it is going to be not roughly quite accurately am P of t minus mt. So, this is how it looks. So, here the P of t represents transmit filter convolved with channel convolved with receive filter. So, this is what you expect in your receive. So, the first thing you can do is write r of t in this form. So, I will show you how to write it. It is a very interesting way of thinking about it. You write it as expected value of a which is independent of m m equals minus n free to infinity P of t minus mt plus you subtract expected value of a from each of these case. So, assuming expected value of a is non-zero this signal decomposes into two non-zero parts. The first part is what? So, assuming expected of a e of a is not zero. So, this is an assumption I am making which will be violated in many signal constellations that we saw. But assuming it is non-zero this r of t breaks down into two parts. The first part is a deterministic periodic part with period 1 by t or with period t. Why am I saying it is deterministic? There is nothing random here. Periodic with period t. So, this part is random. So, I am going to call this a random wriggle that is introduced on top of the periodic 1 by t period t waveform. So, what one can do is roughly take this r of t and do what? How do I extract the period deterministic periodic 1 by t part?  So, you know 1 by t roughly you do not know it exactly. So, you put a rough filter around 1 by t may be quite narrow. So, you know it quite accurately. You know you expect only a minor drift you do not expect huge changes around 1 by t. So, you probably put a very narrow filter around 1 by t you can extract this periodic tone. So, once you get the tone you sample it with that. So, that is the very simple idea in the spectral line method. So, you might say when do you get expected value of a not equal to 0s particularly in optical systems people use what is called on-off communications. The light is there or not there. So, that will correspond to a constellation which is 0 and plus a. So, that will give you a non-zero point. So, those conditions you can extractor can be extracted with a narrow band pass filter. So, the next question is what do you do if expected value of a is 0 then you do not get this part. So, what can be done? Any ideas? What can you do?  You take r of t and you multiply it with itself. So, you get r of t square.  So, this is what you get if you do mod r of t squared. So, now if you take expected value you can expect expected value of a m a n when a m m and n are not equal to be 0. You can expect this to go to 0 which means the expected value of r of t square will have a periodic well it does not necessarily have a periodic pattern I have to further extract the periodic pattern. So, now if you take expected value you will get something. So, let me write it down.  So, even if r of t expected value of a is 0 it is very likely that this will be non-zero. You do expect the value of mod a squared it will be non-zero right for most constant almost every constellation it will be non-zero. So, even if r of t does not have a spectral component at 1 by t it is very very likely that if you take mod r of t squared you will get a spectral component at 1 by t. So, this is non-zero. So, which means this part will be will be it is deterministic periodic with period 1 by t well period t sorry. So, you do a narrow band pass band filter to extract this term. So, r of t comes in you do mod r of t squared and then you do a narrow band pass pass filter you get it. So, these kind of ideas form this idea called spectral line methods for doing timing recovery. Of course, there are decision directed methods also. One such method I want to quickly point out I will point out just one decision directed method for well not really decision directed method for keeping up with timing. So, those are spectral line methods there is one more method called early late I spoke about it briefly yesterday early late gate timing recovery. So, even if you have even if you have a dedicated control channel there might be small drifts in the timing which you can catch with this such methods like early late timing recovery. So, it is common for instance to even in wireless systems to have something something like early late implemented. So, what you do is you have r of t. So, you normally have a timing tone at the receiver and you are expected to sample r of t at that timing tone you will do that also, but to estimate your timing better you will do an early sampling and a late sampling. What do I mean by early and late? So, if this is producing timing tone t this will be t minus sum delta by 2 this will be t plus sum delta by 2. So, within a width of delta minus delta by 2 plus delta by 2 you sample r of t again. So, in most pulse shapes that we saw the early and late gate should roughly produce the same number. So, you might lots of cat needs to be taken there. So, if you keep it carefully if you choose this delta carefully you can expect the early and late gate also to produce the same number. So, if there any different then that error can be used to adjust your timing tone. So, usually there is also an absolute value which is done just to get rid of the complex samples and then you do an error computation and then you do the standard form. So, you put it through a loop filter followed by a VCO which is producing your timing tone. So, any error you compute you deal with like this. So, this is a very simple idea which is implemented in several systems, but I am not talking about the details here this is beyond the scope. So, these are this is one more idea there are several such ad hoc ideas. There is also an idea based on peak estimation differentiating r of t in figuring out where it reaches a peak. It is likely that wherever it reaches a peak it is got right timing. So, there are methods like that ad hoc methods based on that. The next thing I think the last thing I am going to talk about today is carrier recovery once again non decision directed carrier recovery which is basically just called power of n carrier recovery. So, you saw before the way I did my timing recovery I did not need carrier synchronization. So, I did it kind of independently right with the r of t without worrying anything about carrier. Well actually I did not talk about pass band and base band at all. So, many of these techniques can be done even in pass band for instance taking modulus what will it do to e power j completely kill it ok. So, complex exponentials will go away. So, if you are if you have an analytical form if you have sign or cost then there is a problem, but if you did a face filtering face splitting then you have an exact e power j and then you take modulus it will completely disappear. So, the same thing can be done for pass band systems also and you can do timing without doing carrier recovery. So, once you have timing you can do carrier recovery also using this power of n method ok. So, once you have sampled it your sampled waveform is going to have a form like this e power j 2 pi fck t plus theta k summation m equals minus infinity to infinity am pk minus m ok. Once again this is overall response, overall pulse shape ok. So, now, if you imagine a pass band equalizer ok.  So, one hopes and you can approximate p of k as delta ok. So, like I said this works only if you are inside a pass band equalizer ok. So, if you are outside of it maybe this is a bad assumption, but even otherwise you will usually make this assumption ok. So, if this is not a bad assumption one can make this particularly inside a pass band equalizer this is a very reasonable assumption to make because you have already equalized. So, you expect your p of k to be roughly close to delta. So, once you make this assumption you will see that this xk will have a simpler form which you can exploit ok. It is going to be approximately e power j 2 pi fck t plus theta times ak ok the entire convolution because it is a delta becomes just multiplication by ak. So, now, all you have to do is find n such that such that what expected value of ak power n is not equal to 0. So, once you find that n all you have to do is raise xk to the power n which will give you e power j n 2 pi fck t plus theta k right times what? Times expected value of e kn plus the random regal corresponding to the actual realization ok. So, this if you now do a band pass filter at n times fc ok. So, you do a band pass filter at n times fc about n times fc you extract your nfc ok. And then from nfc you can divide by n to go back to fc which dividing timing tones is very trivial right in right at least in digital you can do it very very easily. So, you just divide the carrier and get back to well you have to divide the carrier maybe it is not that trivial, but you can do that even in visualize how to do that ok. So, it is also possible to usually at the output have a PLL to further synchronize everything ok. So, PLL is also used to in this power of n method ok. So, but finding this n is crucial and this n might be easy in several cases for instance in bpsk can you think of an n 2 right. So, if you just square the signal you are going to get a component at 2 fc ok.  So, it is easy to get multiple of fc and then you do a PLL ok. You need a PLL further after that to make sure you have locked on to the right thing after you do a narrow band pass filter ok. So, these are just assorted methods there are more of these things ad hoc methods as well as decision directed methods about which I am not going to discuss ok. Is there any question at all that you want to ask? Welcome to read more books and find out more and figure out what. So, I have just one word of advice for people and people are doing the lab do not try any fancy carrier recovery methods ok. So, best thing I would advise is estimate what your delta f is which you can do using some standard sinusoid frequency estimation methods. Estimate what your delta f is and then compensate for it literally in your demodulation that is what I would advise do not try implementing digital PLLs it is it can be notorious ok. So, the last practical piece which is used in most systems which is missing in what I have done so far is this differential encoding ok. So, we are talking about carrier synchronization and phase synchronization there is one problem with the QAM constellations which you have to tackle independent of all these synchronization essentially especially in decision directed mode ok. So, that is that is the problem because of the symmetry of the QAM constellations. If you look at most QAM constellations ok almost any QAM constellations is basically they have what is called the phase ambiguity of pi by 2 ok. So, symmetric two rotations by pi by 2 right. So, most of the constellations that we talked about are symmetric two rotations by pi by 2 ok. So, if you are now trying to do an equalizer suppose there is just a phase offset some rotation has happened and you are trying to do an equalizer your equalizer can correct for it. In the training mode you would know exactly what the transmitted symbol was and you can subtract, but if you are in decision directed mode you are using the slicer error to feedback your equalizer. If your constellation is rotated by pi by 2 there is a phase difference of pi by 2 there is no way you can recover from it in decision directed mode ok. So, that is the problem that is that needs to be fixed ok. So, suddenly there can be a phase ambiguity of pi by 2 for some reason you may not be able to recover from it once you have once you entered the decision directed mode and that will cause a lot of errors ok. Turns out this can be solved in a very simple way and it is used in almost all systems today ok. So, most people would use this it is called differential encoding. So, what you do is instead of mapping the phase or this constellation point to one bit for instance if you take BPSK you map the bit 0 to plus 1 and bit 1 to minus 1. Instead of doing that absolute mapping you do something called differential mapping ok. So, if you get a bit 1 then you say I will change my constellation point in a specific way ok. So, change of the constellation point signifies your bit as opposed to the absolute point itself that is called differential encoding. So, I will illustrate it with differential BPSK. So, you will see it is really a simple idea and that is that ends up solving this problem ok differential BPSK ok. In regular BPSK what do you do? You have a constellation plus 1 minus 1 you associate a bit 0 to it and associate a bit 1 to it and if you have a bit sequence which is say 0 1 0 0 1 1 0 you associate a phase or a constellation point this VK is a constellation point you associate the see remember what is BPSK doing when you do plus 1 it is not introducing it is doing cos 2 pi of Ct ok if you do minus 1 it is minus cos 2 pi of Ct. So, you can also denote it as 0 pi ok pi pi 0 ok. So, this is the phase that is being introduced by the BPSK and when you decode and you find BK hat what do you do? You simply look at the 0 and then decode to 0 if look at this pi you decode to 1 there is no problem ok you can do each received value independently ok. Simply see constellation point plus 1 you decode to 0 constellation point minus 1 you decode to 1 there is no problem you can just do that without any problem. In differential BPSK you do something which is slightly different ok. So, you update the phase depending on the previous phase by a delta K and there is only a mapping from bit to delta K do 0 1 do 0 pi here and of course, for K equals 0 there is a problem. So, we can set phi minus 1 to be 0 the initial phase is 0. So, the change in the phase is what is controlled by your input bit not the absolute phase itself ok. So, that is what you do in differential BPSK. So, let us take the same BK for the same BK. So, the phi K will be what? Initially it was 0 phi minus 1 is 0 you got a bit 0. So, the phase will be 0 then you got a bit 1. So, the phase becomes pi and then you got a bit 0. So, the phase will be what? It will continue to remain pi ok. So, basically you will send the constellation point plus 1 first and then you will send minus 1 to indicate the change and then you will send minus 1 again ok. So, it is not an absolute mapping from either 0 to plus 1 or 0 to minus 1. So, notice here this minus the first minus 1 corresponded to a bit 1 while the next minus 1 corresponded to a bit 0 ok. So, it can change depending on how things look. So, this is pi then 0 pi pi ok. So, this is how your constellation point would look. So, this would be minus 1 this would be plus 1 am I right plus 1 then plus 1 again and then no minus 1 again and then plus 1 ok. So, those are the constellation points no no no minus 1 I am sorry the last thing is also minus 1. So, the way the constellation point maps to the bit is different, but the phase is what you have to carefully look at ok. So, pi goes to minus 1 pi goes to minus 1. So, that is fine. So, make sure you see this. So, when you decode it you have to do decoding at two levels. The first thing you do is the first step in the decoding is to simply look at the constellation point and decode what bit corresponded to it just blindly like before without worrying about it.  How do you find the bits that were sent? You add an imaginary 0 for the previous thing and in the second step what do you do? You XOR consecutive bits you XOR this bit with the previous bit to get your real bit ok. So, 0 XOR 0 will be 0 1 XOR 1 will be 1 this will be 0 this will be 0 this will be 1 this will be 1 this will be 0 and you go back to your original bit sequence ok. So, the change in the phase was indicated by the bit. So, you decode the phase back and do this XOR to find out if it changed or not right. When you do the XOR you find if it changed or not right if it is different it will be 1 if it is the same it is going to be 0. So, it is a very simple day mapping ok. So, this is differential BPSK. Now, you can also imagine doing differential QPSK ok. How would you do differential QPSK? Yeah delta K will be pi by 2 ok. The phase will change by pi by 2 depending on whether or not your 0 0 0 1 1 0 1 1 and based on that your first and second steps will change slightly ok. You have to be careful about how you design these things it can be done very easily ok. How will you do something like this in 16 QAM? Is it possible? Can you do this in 16 QAM or is it only done for BPSK and QPSK ok. So, what is done usually is in 16 QAM you have 4 quadrants and 4 points in each quadrant ok. So, you can imagine 2 bits denoting the quadrant and 2 further bits denoting what is inside the quadrant. So, what is what is usually done is you encode the 2 bits denoting the quadrant with differential encoding and within the quadrant you do absolute encoding. So, you do a mixture of differential and absolute in more fancy constellation and that is actually done in most systems people do that. The quadrant itself is indicated in a differential way and then the point inside the quadrant is denoted absolutely ok. So, that is how you map from bit sequence to the symbol ok. So, that is differential QAM and all that you can imagine doing this all right. So, I think that is all I wanted to say about carrier phase and timing synchronization like I said it is a it is more of an artistic area right. There is some non-linear components you have to come up with clever tricks if you are smart you can get things implemented faster ok. So, we will stop here for today.