Olivier TREMOIS (@oliviert)
I work for Xilinx! And I should have indicated it at the beginning.That's why I wrote in my first reply:So you have to interface the AD9601 onto an FPGA, preferably...
The problem I see is how to process a stream of samples @ 250Msps using a processor @180MHz.The FPGA should at least perform a downconversion.
Yes. Zynq parts are processors that have an FPGA part tightly coupled.https://www.xilinx.com/support/documentation/data_...https://www.xilinx.com/support/documentation/data_...These...
Hi Yash5,Not only you can use an FPGA but you have to!The AD9601 is a 200/250 Msps ADC, and the max clock rate of the stm32f429 is apparently 180MHz.So you have...
No you should use the figures on the right.The left figure on the downconversion encourage you to compute all the samples and then throw away M-1 out of M.The left...
The two filtering topology (before vs. after) gives exactly the same results in both upconversion and downconversion cases. So for your question about downsampling,...
This architecture is valid just because your filter is symmetric.You gain a lot of time and resource when using specific architectures having a hardware Mult-Acc....
Yes. Your Tx signal impinging on your Rx is very powerful compared to the signal coming back from the targets.
When the signal impinges on the input pin of the ADC, this is just an electric signal which voltage is between [-Vmax; +Vmax].This voltage is transformed into an...
If you want to stick with IIR, I would encourage you to look at Lattice Wave Digital Filters that have very good stability properties, and very narrow transition...
Hi Sumit,I think that the MRC isHence, when one branch is not available, its channel estimate is 0.Let say h2 is null, the equation reduces to:
The obvious answer is 3, but I think you have to add one more because the track on which the circle is moving is itself doing a rotation.So 4 should be the right...
Hi Abhinav90,apparently you want to use Vivado HLS so you should have a look to the User Guide 902 (UG902). Starting at page 614 (for the latest available version...
Kaz,It's true that if you take your filter example even a single multiplier is enough, running at 246.76MHz.I just had a look to the Channel filter specifications...
I don't know what is the target for this processing, but if it is an FPGA I would do this resampling task in multiple steps.125/192 = 5/4 x 5/4 x 5/12 = 5/6 x 5/4...
It's some kind of deconvolution algorithm.You identify the main peak, and then you remove from the FFT result everything that is related to this peak.One processing...
As I said in my post, the linearity of the phase is something that you can handle by increasing slightly the IIR order. You can achieve easily an almost constant...
I would say that implementation wise, when a FIR filter starts to have too many coefficients, an IIR is always a better solution. Typically when you start to think...
I think it is just a question of implementation efficiency.FFT followed by IFFT will end up in a unit gain transform.For N=2^n length transform, FFT and IFFT butterfly...
The error is in the computation of n:n = sqrt(np_watts/2)* ...because here you compute an amplitude, and the power of the complex number (Expectation) is 2.
I forgot to add a lowpass filter as you are on the demodulation part, in order to remove the other part of the spectrum that goes at twice $$f_c$$
Suppose your signal is $$s(nT)$$You want to shift it to the frequency $$f_c$$, the final signal will be $$y(nT)$$If you want to keep the complex signal: $$y(nT)...
There are many parameters to this problem:FPGA clock jitterFrequency that is generatedoutput jitter is input jitter * fclk/f0 (fpga clock/generated clock frequency)Number...
Typically when a[n-1] = 1, then the sgn(x[n]-a[n-1]) will be negative for x[n] less than 1.so for x[n] = 0.7 and a[n-1] = 1, sgn(x[n]-a[n-1]) = -1 even if x[n] is...
I would add that on hardware targets (FPGAs/ASICs) you are not limited to the clock rate of the device. You can create Super Sampling Rate architectures on which...
The coefficients you are using are on the extreme limits of the possibilities of double precision floating point arithmetics.On double precision you have 53 bits...
Hi Amlangford,it is a little more complex than that.There are some weights before the second FFTI attached a pdf file that explains the method and 2 matlab files...
In general the criterion is more in the form of:- passband ripple is less than ...- stopband attenuation is more thanSeeing the downsampling ratio, a single DSP...
Usually OFDM signal (LTE kind:1280 carriers) have 12-13dB of PAPR. This PAPR has to be reduced in order to optimize the operating range of the Power Amplifier.Actually...
Hi Mark,your approach is the right one (rotation FS/4, Half Band, rotation Fs/8, HalfBand), I wrote a little too fast at first place (and perhaps too late!). In...
Hi Loganathan,you have to implement what we call a Super Sampling Rate architecture.So to speak, you have to process multiple samples in parallel.What I understand...
The second equation is the right one in terms of system bandwidth.You need to adapt the FFT length to the sampling rate in order to have:sampling_rate / number_of_bins...
For sure I arrive far after all these nice answers. Downsampling by 2 using a half-band filter is very often (almost always) a good solution. The center tap is 1/2,...
Tim is correct.When your signal is real then you have to sample at least at twice the maximum frequency present in your signal. When the signal is complex (which...
You're right. If you don't want a frequency offset you keep only:theta = offset;in=sin(2*pi*F*t+theta);And then you'll have your phase offset of theta.What is the...
It all depends on the coefficients of your PLL. The code you give is just a way to create a sinusoid with a base frequency plus a frequency shift. In order to have...
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