0:00:13 | and |
---|---|

0:00:13 | um |

0:00:14 | so a graph from everyone and things but anyway style |

0:00:17 | to are representing my work on a turn rate only phase |

0:00:21 | just S and elements rician scheme |

0:00:23 | for sampled data the conversion systems |

0:00:26 | and this work has been done at a university of washington seattle um |

0:00:30 | with michael you ten can which a ring and permission might by of that bit out |

0:00:36 | as a motivation of my talk call |

0:00:38 | present a do we need this yes is good and a lot so that its what's a role of |

0:00:43 | um |

0:00:43 | dish the uh D S B about terms for than about circuits and there |

0:00:47 | and we'll go with the brief or real |

0:00:49 | but it easy to a you that we have selected which in this case would be a segment of thirty |

0:00:53 | C architecture |

0:00:55 | then will propose a low and the lms calibrated to the analog and |

0:01:00 | and |

0:01:01 | then after that will look into that is to back and use be regarded them |

0:01:05 | which uses is under rate and the missed estimation for |

0:01:08 | and finally will complete |

0:01:11 | so |

0:01:12 | and |

0:01:13 | the requirement for as we going to more and more seven and a meter process so you can process |

0:01:19 | we find that |

0:01:20 | a life of an analog design a is becoming harder and harder because |

0:01:24 | for even simpler blocks like operational amplifier |

0:01:28 | you find that the voltages is that shrinking |

0:01:30 | you are strings are reducing and so |

0:01:33 | the challenges is becoming higher and hard to reach a higher again |

0:01:36 | at the same time for the should design a is becoming a relatively easy you have a much higher sampling |

0:01:41 | speed |

0:01:42 | and it can be that |

0:01:43 | um you can really a not achieve i to but |

0:01:48 | so that |

0:01:48 | the basic motivation for this work is this to use a core design approach |

0:01:53 | um a to be use that dish to the S got tends to kind of correct then a lot of |

0:01:57 | functions that we can |

0:01:59 | so before or we step into they at C architecture it is a very general overview of |

0:02:04 | different type of D Cs |

0:02:06 | and this architecture is just a sorry |

0:02:09 | the still clutching is actually a a just compare is actually it |

0:02:13 | for a low to medium band with application |

0:02:16 | and for high resolution |

0:02:17 | applications on a so |

0:02:19 | it's a very generate go we just to give an idea of we stand |

0:02:22 | and if you look we have |

0:02:23 | different types of a arctic for a T Cs like flash |

0:02:27 | i line |

0:02:28 | successive approximation just tear and segment the at C |

0:02:31 | and they have been compared for different parameters like throughput resolution solution they can see power here |

0:02:37 | and |

0:02:37 | for |

0:02:38 | like for low to medium and at that location and high resolution |

0:02:42 | you find a sigma delta a C a one of the most of a lot to that |

0:02:46 | we can have a |

0:02:47 | and so you know use we are actually targeting like for wireless lan uh approximation of like nice i like |

0:02:53 | that |

0:02:54 | and eleven it affected them |

0:02:58 | before we step into the at C are look into that |

0:03:01 | if see architecture the some critical implementation choices is that we should we need to decide |

0:03:06 | and to of the definitions that we have a |

0:03:08 | as for or something ratio |

0:03:10 | which is defined |

0:03:11 | as as a ratio of sampling frequency or what twice a signal time |

0:03:14 | no what's simple of this number is is that |

0:03:17 | i do a so you find that you can get a high |

0:03:20 | uh |

0:03:22 | at the same time |

0:03:23 | for white that of that iterations |

0:03:25 | it means that we need a a has in frequency |

0:03:29 | because if a is increasing |

0:03:30 | it's got at first increases as well |

0:03:33 | so here in this design |

0:03:35 | the focus |

0:03:35 | more on maximizing minimizing the power |

0:03:38 | rather than maximizing this P |

0:03:40 | and so that's of reason real select a low sir of one eight for was design |

0:03:46 | and the question that we want to answer is |

0:03:48 | how little can we should be in of a pen |

0:03:51 | like a is it why able to use like |

0:03:53 | around ten a can be enough ten or twenty |

0:03:57 | and so will will like is twenty six db gain or of easy but generally like a sigma don't applications |

0:04:02 | the are in the range of like fifty to seventy db |

0:04:06 | which is a to achieve a as we use a scaled down the supply |

0:04:10 | so we'll see that if such a thing just yeah use a to be all them uh oh and that |

0:04:14 | such a again |

0:04:15 | if you try to use the in and bold is in the system can you can you can be them |

0:04:19 | which today |

0:04:20 | and and the whole |

0:04:21 | uh process we power |

0:04:23 | yeah fish |

0:04:25 | before we four still uh so this like of a simple um evil you |

0:04:30 | all a second order |

0:04:31 | see my that the U C to large |

0:04:34 | so that i made a C it can be just |

0:04:36 | plus five in terms so |

0:04:38 | it's a two input |

0:04:40 | one our system |

0:04:41 | so these are like to uh a time samples sampled input |

0:04:45 | and then you get a a a a two a a and it can be it in terms of runs |

0:04:49 | functions |

0:04:50 | well the signal process |

0:04:51 | S T F |

0:04:52 | and noise times |

0:04:54 | you |

0:04:55 | so will will to of this out |

0:04:57 | and a be five |

0:04:58 | so if you look into the right side here so |

0:05:01 | so a large |

0:05:02 | score the V four |

0:05:03 | oh |

0:05:04 | no that's what we is thing but is just it's of C |

0:05:08 | you take that out of the sum |

0:05:09 | and you give it to the to integrate is |

0:05:11 | do of one |

0:05:12 | two |

0:05:13 | let's signal that someone O G N S one year |

0:05:16 | time being |

0:05:17 | so this is there since that to integrate as |

0:05:19 | well |

0:05:20 | i not as the |

0:05:21 | we take the output of the someone and we some all the all |

0:05:24 | a and you give it to a for quantizer |

0:05:27 | for like to D C |

0:05:28 | and the we do a C is then |

0:05:31 | back |

0:05:31 | to at least a to compare compared |

0:05:33 | oh sorry |

0:05:35 | and by to |

0:05:36 | which is then some time |

0:05:39 | they have to the right is of the still a for all us |

0:05:43 | as you can see from the |

0:05:45 | from the signals signs here |

0:05:46 | on the Y axis is the a is a range of and you hear |

0:05:50 | and the X is just a times |

0:05:53 | so you see that the was we one and B two |

0:05:56 | have a very small signals planes |

0:05:58 | which means that we do i mean it to use as the requirements for the |

0:06:02 | for the integrate is that we have a |

0:06:04 | all |

0:06:05 | and it also |

0:06:06 | the using this string mean |

0:06:08 | that's so and using |

0:06:10 | a and ones on the entire assist |

0:06:12 | or |

0:06:13 | that that's one of the pretty good advantages of having a a for long |

0:06:17 | the second row |

0:06:18 | that if you can the process |

0:06:20 | from input of the quantizer |

0:06:22 | to a the the second integrate two |

0:06:25 | we find that |

0:06:26 | the last |

0:06:27 | is just a quantization noise |

0:06:30 | so we'll see what's a man to this is to |

0:06:32 | this feature in the next i |

0:06:34 | but is the two things that's well |

0:06:37 | and |

0:06:38 | so for this system |

0:06:39 | we can and a like the signal as a function which is the cost |

0:06:42 | from the input that |

0:06:44 | to but |

0:06:45 | skis |

0:06:45 | and the also |

0:06:46 | and to yeah i post |

0:06:48 | a given by a second one scene |

0:06:51 | if you like to do not at here for we find |

0:06:54 | while see that all put yeah training |

0:06:56 | but |

0:06:57 | position of two done |

0:06:58 | X of the month like of the signal process |

0:07:00 | okay |

0:07:01 | so what implies lies is as the input |

0:07:04 | goes to all without |

0:07:05 | a frame |

0:07:07 | and the one position on |

0:07:08 | is not filtered by a signal |

0:07:10 | i |

0:07:11 | um |

0:07:12 | so you can think of this as like it basically a portion that in but quantisation noise |

0:07:16 | with |

0:07:17 | to go that |

0:07:18 | and in that was is it is a resolution of eighties |

0:07:22 | the next question that the we have to so is is this |

0:07:25 | system |

0:07:27 | sufficient for for a requirement of realising a one bit |

0:07:30 | snr or S india |

0:07:33 | so think is like this system but then always are of eight can realise and nine but that's the not |

0:07:37 | so we need an additional two bits |

0:07:39 | so what should we do |

0:07:41 | so what we do here is we |

0:07:43 | we into it to a large you just on a stochastic signal at at at C |

0:07:48 | so it's very simple like take the system from the previous slide |

0:07:51 | we are another system a |

0:07:55 | and then to do that |

0:07:56 | what we do is at the input of this second stage |

0:07:59 | we just stick you would you all |

0:08:01 | Z you minus two from the previous it |

0:08:03 | and added to the input of the second stage |

0:08:06 | now |

0:08:07 | feed you it in a more or any uh a a little bit more mathematics a |

0:08:12 | and if you yeah to digital filters |

0:08:14 | S of two D which actually matches |

0:08:17 | uh a that a lot signal as a function of the second stage and then T of one D which |

0:08:22 | match is the noise |

0:08:23 | a function of the first stage |

0:08:24 | and we some though two |

0:08:26 | why of C |

0:08:27 | then after to doing some at which we go now |

0:08:30 | we find that the we can get a higher order of my thing which implies a high resolution |

0:08:35 | ones |

0:08:36 | uh let's just finish the system here |

0:08:38 | and so once we get this out |

0:08:40 | this is just a decimation estimation for to and it that's mixed down by eight |

0:08:44 | as you can see a three state to to the first as the cascade to get the call to just |

0:08:48 | but you for that about how when only face but to |

0:08:51 | the the estimates it's by two for by a single uh a five compensation for |

0:08:55 | but isn't it split into three state is is just to my as the power |

0:08:58 | for |

0:09:00 | let's look into the summation here and you see here is that the input signal |

0:09:05 | X of Z |

0:09:06 | C just a a segment as a function |

0:09:08 | and |

0:09:08 | as we saw the previous slide |

0:09:10 | the signal process |

0:09:11 | and is you need so the signal that signal X of C |

0:09:14 | goes out with that |

0:09:15 | you need |

0:09:17 | a second term here |

0:09:19 | which is a forced one quantization noise as you in this is a ideal system |

0:09:23 | would find that |

0:09:24 | if you assume that the and T F one of me is equal to T of one of the |

0:09:28 | and S you of two of these equal to have two of this at this and sits out |

0:09:32 | and so there's is not one position on the first to from position noise doesn't come |

0:09:38 | the total component reduced you to of C |

0:09:41 | sees a four door that a function here |

0:09:43 | and it effectively means that now we are able to |

0:09:46 | noise shape by a fourth order |

0:09:49 | so |

0:09:49 | that's it's it's a good thing in the sense that we have |

0:09:53 | we can just take to stable second out of trance that systems |

0:09:56 | put them together and get a higher order |

0:09:59 | a a higher or the noise shaping which implies a a high snr |

0:10:02 | what what |

0:10:03 | the disadvantage of the system is this one will be in a cyst uh it is the design |

0:10:08 | it will introduce mismatch between the and a lot |

0:10:11 | a fancy |

0:10:12 | chen and that is to |

0:10:14 | function |

0:10:15 | so how does that come to the house |

0:10:17 | so as we see you know like for a very high gain or and we see that |

0:10:21 | the noise or or for uh |

0:10:24 | a noise of the system is done to but i'm long |

0:10:28 | so here here it's six |

0:10:29 | this is the signal back from zero |

0:10:32 | to ten made |

0:10:34 | and on the bias |

0:10:34 | the or like to rent C V |

0:10:36 | D |

0:10:37 | so right now |

0:10:38 | we can see that for a very large gain it's done it but um and noise |

0:10:42 | but at that it use uses a pretty six db |

0:10:44 | the one position noise |

0:10:46 | starts don |

0:10:47 | on |

0:10:49 | on the right to easy you why that's a reason |

0:10:51 | so we see that |

0:10:52 | that approximation emission that we came a are cross across year one minus the was where |

0:10:58 | all of it true because that are outside |

0:11:00 | as an iir are filter |

0:11:02 | because of that that's that's thing |

0:11:04 | and the gain of whatever |

0:11:05 | "'cause" the system that's |

0:11:07 | to right |

0:11:08 | so what happens is that one position as of the first stage weeks without it |

0:11:12 | and it produces |

0:11:13 | by uh |

0:11:14 | has an impact on a phone |

0:11:19 | so |

0:11:19 | what we do is we take the help of and of the audit |

0:11:23 | to really |

0:11:24 | or a the performance impact that we have |

0:11:27 | so i'll go to the |

0:11:28 | the detail in the blocks of the plots in the next slide |

0:11:31 | what |

0:11:32 | in this like we just want to get a general overview of what we want to do |

0:11:35 | so what we do is we deactivate the input and we inject |

0:11:38 | at to to do great |

0:11:40 | no no no C |

0:11:41 | which is generated on to |

0:11:43 | from a linear feedback shift register |

0:11:46 | at the same time we take the sequence |

0:11:48 | to uh |

0:11:49 | to a set a file for this |

0:11:51 | uh i T have to the in in of one B |

0:11:53 | the output of this a five for is compared with that |

0:11:56 | a with that and a lot of by one of the Y to see |

0:11:59 | and then we use that a missing write them to get you can be the distance |

0:12:03 | a |

0:12:04 | so right |

0:12:05 | so to summarise rate yeah actually using |

0:12:07 | sign to the ms one |

0:12:10 | for |

0:12:10 | a listener was it's one of the most easiest to implement that are most of if |

0:12:16 | and it's it's from you got to maybe compute the next year or efficient |

0:12:20 | from the previous state |

0:12:21 | use that the patient size |

0:12:22 | you know as there |

0:12:23 | if getting in the design and |

0:12:26 | uh and that it right C |

0:12:28 | we take the sign of |

0:12:29 | yeah yeah |

0:12:30 | that |

0:12:32 | the way is about the works is it each be because of the operates |

0:12:36 | to it finds that error is minimised that a miss things |

0:12:39 | and the coefficients is actually get a response to the |

0:12:43 | by so as a function of the signal doesn't |

0:12:45 | that we expect on the |

0:12:47 | so after the long i do calibration |

0:12:50 | you see that the to uh signal thus |

0:12:53 | this same as that of one |

0:12:54 | and for what they stiff and then you |

0:12:57 | oh |

0:12:59 | there is much what do you know how we implement the |

0:13:02 | uh |

0:13:03 | the filters |

0:13:04 | so we inject the thirty two bit to a L that it and m-sequence a thing |

0:13:09 | yeah |

0:13:11 | screen and rate to five to |

0:13:13 | the output of this a five |

0:13:15 | is that can be a the output |

0:13:18 | that you see why |

0:13:19 | the Z Y two Z |

0:13:20 | and there is then you meant to have a isn't going |

0:13:23 | and the coefficients of an adaptive guys |

0:13:26 | so to to use the truncation errors |

0:13:28 | in there five for it is use an eight to five |

0:13:32 | one disadvantage that the |

0:13:34 | system them can have a |

0:13:35 | is that you in for a set of the asians |

0:13:37 | we are actually sound the system |

0:13:39 | i a sampling frequency of the N T one fifty two hundred meg |

0:13:44 | a what as is that |

0:13:45 | you do you have a very low or and |

0:13:47 | because now we are using very |

0:13:50 | simple simple fires and optimising and |

0:13:52 | the |

0:13:53 | oh |

0:13:53 | a channel addition |

0:13:54 | but |

0:13:55 | three can |

0:13:56 | approximate three times if you do a |

0:13:58 | a force that |

0:13:59 | as compared to that |

0:14:01 | so what should we do |

0:14:02 | how should be uh |

0:14:04 | uh or should be in signal processing techniques here |

0:14:07 | to make sure that you get a good efficient says |

0:14:10 | what we do a is in that to mention the police that you just |

0:14:14 | about |

0:14:14 | oh |

0:14:15 | we are using a noise cancellation the also |

0:14:18 | which is same as |

0:14:19 | basically C the N T F and S T E |

0:14:22 | uh yeah on again as and C S |

0:14:25 | and the are basically using that a |

0:14:27 | as we talked in the previous slide |

0:14:29 | no but ones get a is given decimation fig |

0:14:32 | which on |

0:14:34 | so the proposed approach what we do it |

0:14:38 | we use one these techniques |

0:14:39 | do really to do a convolution of |

0:14:41 | the noise |

0:14:42 | the noise cancellation fit |

0:14:44 | and india for this stiff |

0:14:45 | yeah |

0:14:46 | and that is for that |

0:14:48 | and get a what if easy |

0:14:51 | then we do the same per |

0:14:53 | we reject the a random sequence |

0:14:55 | we get the desired signal |

0:14:57 | and B J the all output of the four and a stage |

0:15:01 | and we make sure that sees the C |

0:15:04 | and then compared what the stages |

0:15:06 | do you do in N |

0:15:07 | and |

0:15:09 | now this approach is very similar to what a good subband adaptive filter |

0:15:13 | but |

0:15:13 | one pretty good point two |

0:15:15 | that we are using or sampling in this case |

0:15:18 | so using or so |

0:15:20 | i |

0:15:20 | it tells us to use the you using |

0:15:22 | right |

0:15:22 | and it helps service |

0:15:23 | to ensure |

0:15:25 | that of |

0:15:25 | that |

0:15:26 | the white one of C |

0:15:28 | oh which we used to basically |

0:15:30 | uh this you estimate |

0:15:32 | is not a very aggressive anti aliasing filter |

0:15:34 | and it just has to be very many |

0:15:37 | so |

0:15:37 | that this approach |

0:15:39 | for a or so as well |

0:15:43 | so that is the proposed a one |

0:15:45 | some |

0:15:47 | and |

0:15:47 | the the system that we show that us like reject |

0:15:51 | it and see |

0:15:52 | here |

0:15:53 | we are a a lot of the estimate it |

0:15:55 | and we lost |

0:15:55 | a if it's like filter |

0:15:57 | take out right |

0:15:58 | the same time we take the out of that of |

0:16:01 | well as the |

0:16:02 | this yeah |

0:16:03 | so for or or in this this meeting but |

0:16:06 | a of this |

0:16:09 | right to that it are and take their |

0:16:11 | compute coefficient |

0:16:12 | so we do that for both the parts of are here |

0:16:15 | and finally |

0:16:16 | we can speak |

0:16:19 | good thing about this is we found that |

0:16:21 | but the meant in a similar |

0:16:23 | it's you using this to two at which means that you can |

0:16:26 | re read to not to my |

0:16:28 | based on the whole system in innovation |

0:16:33 | um |

0:16:34 | do does have a small one right |

0:16:36 | because of the increase in the number of taps of you and C T E M Z but was that |

0:16:40 | have can is based on |

0:16:42 | and it can he's the optimized when we do not you |

0:16:45 | issue |

0:16:46 | we friend the power decreases when you decoding |

0:16:49 | case |

0:16:50 | oh |

0:16:51 | that's television we shouldn't a points the number of points in or |

0:16:55 | are pretty much the same for all all the different techniques |

0:16:58 | so |

0:17:00 | is proposing but the system that we have |

0:17:02 | yeah we have that a lot |

0:17:03 | yeah |

0:17:04 | we we see that |

0:17:05 | using the low you know that |

0:17:07 | introduces some some in what errors which is a mismatch in the |

0:17:10 | and and and to process function |

0:17:12 | and here as the but different flavours of the back and that we have a |

0:17:15 | and to again an F P G |

0:17:17 | and we got and mention that a misty with the one face but to a and what if is better |

0:17:22 | or |

0:17:26 | there is a |

0:17:27 | they should signal to noise ratio in of you of this nation |

0:17:30 | so without any yeah |

0:17:31 | a missing uh without any kind vision find a signal to noise ratio |

0:17:35 | yeah |

0:17:36 | as actually don't around fifty six points |

0:17:38 | db |

0:17:39 | after calibration |

0:17:40 | uh |

0:17:41 | we see that |

0:17:42 | all the three seems give hear a D or form |

0:17:44 | eleven bits |

0:17:46 | oh six is a T V C |

0:17:47 | i |

0:17:48 | i |

0:17:48 | C six |

0:17:49 | i |

0:17:53 | um |

0:17:54 | so here is a matrix fixed calibration |

0:17:57 | sampling frequency V using as |

0:17:59 | one |

0:17:59 | have |

0:18:00 | oh of the option that i |

0:18:03 | i |

0:18:04 | what |

0:18:05 | what |

0:18:06 | or supply voltage |

0:18:07 | one point two five or to |

0:18:10 | a spare |

0:18:12 | i meant one had in a seamless |

0:18:16 | as a comparison |

0:18:17 | the it's uh |

0:18:18 | a a here is the forced to be so we use like a in a six db |

0:18:23 | but it's just a lot of them |

0:18:25 | to yes |

0:18:26 | and before that up to my |

0:18:28 | the rest of the cost of i'd a reference for years |

0:18:32 | and |

0:18:32 | actually a uh and the quantizer |

0:18:35 | and i think this and the number can be really optimized to last |

0:18:39 | what's for a forty five |

0:18:40 | design |

0:18:41 | yeah |

0:18:44 | we uh as compared to the other the words we see that we have a |

0:18:47 | can't |

0:18:48 | uh a or savings for that |

0:18:51 | for the by |

0:18:52 | we do a |

0:18:53 | approximate analysis of finding the power for years |

0:18:58 | so the use that are |

0:18:59 | i see that |

0:19:01 | uh you |

0:19:02 | a power as it can be at fourteen time |

0:19:04 | uh a small errors |

0:19:06 | G |

0:19:07 | i become got this the actions of you for many words |

0:19:12 | what is |

0:19:12 | you get on that |

0:19:15 | a before for the demise |

0:19:16 | as this |

0:19:18 | so we do not that it at your had |

0:19:20 | because of some |

0:19:21 | for does that you have to put to match |

0:19:23 | it |

0:19:26 | so is a final completion format |

0:19:28 | um are don't was to the use of a six E uh you know |

0:19:33 | sees |

0:19:34 | you said that |

0:19:35 | addition white them to go go from the gain errors |

0:19:37 | and uh we proposed something |

0:19:39 | techniques |

0:19:40 | which uses like month at it uh are it important is |

0:19:44 | only polyphase |

0:19:45 | i |

0:19:47 | and we find that |

0:19:48 | using this you |

0:19:49 | that as in using at or |

0:19:51 | the machine |

0:19:52 | especially for high fit |

0:19:54 | by |

0:19:57 | thank you |

0:19:58 | if you have any question |

0:20:02 | sure |

0:20:08 | oh |

0:20:13 | yeah |

0:20:21 | also |

0:20:22 | yeah we compared to the convention |

0:20:26 | the |

0:20:27 | then use |

0:20:28 | i don't |

0:20:30 | i a moving bad to are of people |

0:20:33 | yeah the whole system can see |

0:20:37 | uh |

0:20:38 | okay |

0:20:38 | okay |

0:20:42 | i |

0:20:46 | just space |

0:20:53 | and |

0:20:57 | min |

0:20:58 | yeah i would say like a uh i think though the presence and this project has been on like a |

0:21:02 | design between that a lot in by |

0:21:05 | so if you compare the uh |

0:21:07 | i figure of matter it's with the current architecture use one just |

0:21:10 | the an up front and that we have |

0:21:12 | it's actually not uh it's not |

0:21:14 | as good as |

0:21:15 | scum it's and the ball but but it's not as good as the best ones and there |

0:21:19 | but the more mean as is here is how can you really meant like a back and |

0:21:23 | when you have a like a very cheap and a |

0:21:32 | i |

0:21:33 | oh |

0:21:34 | i |

0:21:35 | oh |

0:21:35 | thank you |