Reply by Fred Marshall May 23, 20092009-05-23
somaguy wrote:
> So I've recently been asked to research beamforming as a possible > application for hardware-based acceleration. I have a rough > understanding of the concept of (receiver) beamforming but I'm at a > little bit of a loss as far as how it is applied practically. For > commercial beam-forming systems what is the range of array sizes used? > > From another colleague I've heard that the input bandwidth can be > quite large and so the input bandwidth to the processing elements > must be, well, wide. How is this typically dealt with? Also, for > large data input sets, is it possible to segment the data to several > processing elements (DSPs, FPGAs, etc) and process the data > independently and superimpose it later, or must it be done as a > single memory set? > > Also, any links/references to commercial devices that do the > beamforming data processing is appreciated. > > Thanks for your time, this analog/digital signal processing stuff is > very interesting but kind of hard :-\ > > -Ivan
"hardware based acceleration"? So, are you trying to find a problem in search of a solution (yours)? One key question would be: Are you trying to form multiple, overlapping beams or just a single beam or two? The approach could well depend on the answer to this. The former is much more compute-intensive. The latter less so. Fred
Reply by Jerry Avins May 23, 20092009-05-23
Jerry Avins wrote:
> somaguy wrote: >> So I've recently been asked to research beamforming as a possible >> application for hardware-based acceleration. I have a rough understanding >> of the concept of (receiver) beamforming but I'm at a little bit of a >> loss >> as far as how it is applied practically. For commercial beam-forming >> systems what is the range of array sizes used? > > The ones used in medical ultrasound are about two inches long. There are > triangular (omnidirectional) antenna arrays on top of cell phone towers > that appear to be about 3 or four frrt on a side. There are picket radar > antennas that, laid horizontally, would make a modest-sized parking lot. > Take your pick. > >> From another colleague I've heard that the input bandwidth can be quite >> large and so the input bandwidth to the processing elements must be, >> well, >> wide. How is this typically dealt with? > > With wide-band components. > >> Also, for large data input sets, is >> it possible to segment the data to several processing elements (DSPs, >> FPGAs, etc) and process the data independently and superimpose it >> later, or >> must it be done as a single memory set? > > Whatever works. In some radar arrays, each antenna segment is separately > powered and individually phased. > >> Also, any links/references to commercial devices that do the beamforming >> data processing is appreciated. >> >> Thanks for your time, this analog/digital signal processing stuff is very >> interesting but kind of hard :-\ > > And you are jumping into one of the harder parts. You need to find > someone whose feet you can sit at. What books have you read?
cfy30 wrote: > Jerry, > > Let me rephrase my question. I know the frequency response of a > bandpass filter, how to find its low pass equivalent? Notice that I > don't have the transfer function of the filter. The frequency response is a plot (two plots, actually: amplitude and phase) of the transfer function. Estimate the break points in the s domain and plot to see if you estimated well enough. Iterate. Jerry -- Engineering is the art of making what you want from things you can get. ����������������������������������������������������������������������� -- Engineering is the art of making what you want from things you can get. �����������������������������������������������������������������������
Reply by Eric Jacobsen May 23, 20092009-05-23
"somaguy" <ivan@dinigroup.com> wrote in message 
news:27idncVgZI-WwYrXnZ2dnUVZ_hqdnZ2d@giganews.com...
> So I've recently been asked to research beamforming as a possible > application for hardware-based acceleration. I have a rough understanding > of the concept of (receiver) beamforming but I'm at a little bit of a loss > as far as how it is applied practically. For commercial beam-forming > systems what is the range of array sizes used? > > From another colleague I've heard that the input bandwidth can be quite > large and so the input bandwidth to the processing elements must be, well, > wide. How is this typically dealt with? Also, for large data input sets, > is > it possible to segment the data to several processing elements (DSPs, > FPGAs, etc) and process the data independently and superimpose it later, > or > must it be done as a single memory set? > > Also, any links/references to commercial devices that do the beamforming > data processing is appreciated. > > Thanks for your time, this analog/digital signal processing stuff is very > interesting but kind of hard :-\ > > -Ivan
A common modern example is an 802.11n MIMO AP or client. They don't all employ beamforming (it's an optional element in the standard) but the only thing that would change would be the internal digital processing. As others have pointed out, the answers to your questions can vary quite a bit depending on the application.
Reply by Jerry Avins May 23, 20092009-05-23
somaguy wrote:
> So I've recently been asked to research beamforming as a possible > application for hardware-based acceleration. I have a rough understanding > of the concept of (receiver) beamforming but I'm at a little bit of a loss > as far as how it is applied practically. For commercial beam-forming > systems what is the range of array sizes used?
The ones used in medical ultrasound are about two inches long. There are triangular (omnidirectional) antenna arrays on top of cell phone towers that appear to be about 3 or four frrt on a side. There are picket radar antennas that, laid horizontally, would make a modest-sized parking lot. Take your pick.
> From another colleague I've heard that the input bandwidth can be quite > large and so the input bandwidth to the processing elements must be, well, > wide. How is this typically dealt with?
With wide-band components.
> Also, for large data input sets, is > it possible to segment the data to several processing elements (DSPs, > FPGAs, etc) and process the data independently and superimpose it later, or > must it be done as a single memory set?
Whatever works. In some radar arrays, each antenna segment is separately powered and individually phased.
> Also, any links/references to commercial devices that do the beamforming > data processing is appreciated. > > Thanks for your time, this analog/digital signal processing stuff is very > interesting but kind of hard :-\
And you are jumping into one of the harder parts. You need to find someone whose feet you can sit at. What books have you read? Jerry -- Engineering is the art of making what you want from things you can get. &#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;&#4294967295;
Reply by Tom May 23, 20092009-05-23
On May 23, 11:14&#4294967295;am, "somaguy" <i...@dinigroup.com> wrote:
> So I've recently been asked to research beamforming as a possible > application for hardware-based acceleration. I have a rough understanding > of the concept of (receiver) beamforming but I'm at a little bit of a loss > as far as how it is applied practically. For commercial beam-forming > systems what is the range of array sizes used? > > From another colleague I've heard that the input bandwidth can be quite > large and so the input bandwidth to the processing elements must be, well, > wide. How is this typically dealt with? Also, for large data input sets, is > it possible to segment the data to several processing elements (DSPs, > FPGAs, etc) and process the data independently and superimpose it later, or > must it be done as a single memory set?
Almost all the questions you ask (bandwidth, number of array elements, implementation) depend very much on the application. Some applications of beamforming include wireless (cellular, WLAN, point-to-point etc) communications, radar/sonar, direction of arrival estimation, etc, etc. Even within wireless communications you have OFDM, CDMA, SC etc based techniques, for each of which the processing requirement for beamforming may be different. Further, beamforming can be implemented using analogue phase shifters at RF, or by individual (usually digital) control of each element (where you could implement either phase shifting or true time delay, the latter being better for wide bandwidths). You can also consider some of the advanced MIMO techniques (including precoding) as examples of generalized multi-mode beamforming. So given all that, you need to provide some details of the applications you are targeting before you can receive sensible and useful answers to your questions. -T
Reply by dbd May 23, 20092009-05-23
On May 22, 7:14 pm, "somaguy" <i...@dinigroup.com> wrote:
> So I've recently been asked to research beamforming as a possible > application for hardware-based acceleration. I have a rough understanding > of the concept of (receiver) beamforming but I'm at a little bit of a loss > as far as how it is applied practically. For commercial beam-forming > systems what is the range of array sizes used? > > From another colleague I've heard that the input bandwidth can be quite > large and so the input bandwidth to the processing elements must be, well, > wide. How is this typically dealt with? Also, for large data input sets, is > it possible to segment the data to several processing elements (DSPs, > FPGAs, etc) and process the data independently and superimpose it later, or > must it be done as a single memory set? > > Also, any links/references to commercial devices that do the beamforming > data processing is appreciated. > > Thanks for your time, this analog/digital signal processing stuff is very > interesting but kind of hard :-\ > > -Ivan
How about starting with some research at places like http://en.wikipedia.org/wiki/Beamforming And reading some of the references there as well, and then coming back with more specific questions? Dale B. Dalrymple
Reply by somaguy May 22, 20092009-05-22
So I've recently been asked to research beamforming as a possible
application for hardware-based acceleration. I have a rough understanding
of the concept of (receiver) beamforming but I'm at a little bit of a loss
as far as how it is applied practically. For commercial beam-forming
systems what is the range of array sizes used? 

From another colleague I've heard that the input bandwidth can be quite
large and so the input bandwidth to the processing elements must be, well,
wide. How is this typically dealt with? Also, for large data input sets, is
it possible to segment the data to several processing elements (DSPs,
FPGAs, etc) and process the data independently and superimpose it later, or
must it be done as a single memory set?

Also, any links/references to commercial devices that do the beamforming
data processing is appreciated.

Thanks for your time, this analog/digital signal processing stuff is very
interesting but kind of hard :-\

-Ivan