Oversampling & moving-average-filter

Started by Rob in comp.dsp9 years ago

Hi, I've spent some time reading about oversampling and I think I understand the fundamentals. Oversample by some factor > desired...

Hi, I've spent some time reading about oversampling and I think I understand the fundamentals. Oversample by some factor > desired bandwidth, decimate and increase ENOB (with certain assumptions about dithering, etc). My signal of interest is slowly varying (1-2 Hz), and I'm using a 10-bit ADC, oversampling at 10 ksamples/sec. Two questions: 1. For oversampling, some document


Oversampling in communication systems

Started by Mas Bas in comp.dsp12 years ago 1 reply

Hi all, I would like to know about the oversampling used in communication system. There are 2 technique which commonly used. 1. Using...

Hi all, I would like to know about the oversampling used in communication system. There are 2 technique which commonly used. 1. Using (N-1) zero padding, to get N factor oversampling and finally use a digital filter to filled up the zeros. 2. Repeat the sample (N-1) times to get N factor oversampling and also finally use a digital filter to adjust the value in oversampling location....


Oversampling

Started by George in comp.dsp10 years ago 23 replies

What is the highest oversampling rate in commercial use on high fidelity (15 kHz) audio nowadays? I'm not looking for anything leading-edge or...

What is the highest oversampling rate in commercial use on high fidelity (15 kHz) audio nowadays? I'm not looking for anything leading-edge or very pricey. Just commercially available ADCs that are premium priced but aren't extremely expensive. A few years ago I recall 8X oversampling was considered good without having a big cost penalty. I imagine that rate would be higher today? ...


Oversampling in WCDMA receiver

Started by HSDPA-boy in comp.dsp10 years ago 7 replies

Hi, I have a question about oversampling when doing RRC filtering and correlations in WCDMA receiver. Both these operations are done at...

Hi, I have a question about oversampling when doing RRC filtering and correlations in WCDMA receiver. Both these operations are done at base band in the digital domain. In the literature I've read that the signal is oversampled say 4 or 6 times when doing both the RRC filtering and subsequent correlation. What is the motivation for oversampling in these two cases? The use of an oversampled sign...


OFDM transmitter oversampling

Started by cocioc in comp.dsp11 years ago

Hello, I have a question regarding the OFDM transmitter. In order to reduce the burden on the reconstruction filters, oversampling is used...

Hello, I have a question regarding the OFDM transmitter. In order to reduce the burden on the reconstruction filters, oversampling is used before feeding the data to the DAC. Oversampling, however, creates images of the baseband signal. To remove these images, low pass filters are placed after the rate up converter. These filters are FIR systems, and, when applied to the signal, "smudge" it...


Oversampling in an ADC to improve performance

Started by Jorge Rivas in comp.dsp8 years ago 10 replies

Hi all, I have a communications system that is streaming analog data. On the receiver side, this data is converted by an ADC with an...

Hi all, I have a communications system that is streaming analog data. On the receiver side, this data is converted by an ADC with an oversampling of 4 related to the conversion rate of the DAC on the transmitter. As it is a system under testing (with variable speed), we don't have a proper steep analog filter before the ADC, so the oversampling will help to achieve a better performance. In...


Does oversampling bring diversity gain?

Started by Benjamin Jiajia in comp.dsp10 years ago 15 replies

As oversampling produces several baud rate signal sequences (for example, oversampling by a factor of 2 produces two baud rate sequences with...

As oversampling produces several baud rate signal sequences (for example, oversampling by a factor of 2 produces two baud rate sequences with an offset of half baud duration), could these sequences be viewed as a kind of diversity? and what's its gain? _____________________________________ Do you know a company who employs DSP engineers? Is it already listed at http://dsprelated.com/e...


only I mixer instead of IQ mixer?

Started by mary1234567 in comp.dsp11 years ago 2 replies

I have tested use only cos(2*pi*fmix*n/fs) to demodulate a BFSK input signal. And it worked. Question is how much worse will it be? Will it...

I have tested use only cos(2*pi*fmix*n/fs) to demodulate a BFSK input signal. And it worked. Question is how much worse will it be? Will it be 3dB worser? Can I compensate this by oversampling instead? For example will a double oversampling give 3dB more SNR. Any answer is welcome! /Mary


IIR not fully causal?

Started by Carlos Moreno in comp.dsp12 years ago 40 replies

I've been thinking about this crazy idea that I assume has to be something that someone did already. Say that I'm trying to do oversampling;...

I've been thinking about this crazy idea that I assume has to be something that someone did already. Say that I'm trying to do oversampling; let's take, as an example, oversampling by a factor of 4. So, what we do is, just put a sample of the signal, then three samples with zero, then apply a low-pass filter (with cutoff pi/4). This low-pass filter should, in principle, be a 0-phase ...


Is higher oversampling ratio better in signal fidelity in digital world?

Started by yhe in comp.dsp11 years ago 29 replies

For digitized audio signal, intuitively higher oversampling ratio, the digitized signal is closer to original signal, therefore,...

For digitized audio signal, intuitively higher oversampling ratio, the digitized signal is closer to original signal, therefore, higher fidelity. In digital work, for example, transferring digital data through wcdma/cdma network, the digital data / digitized voice data will be oversampled, maybe resampled, then modulated and transmitted. Will higher oversampling rato offer better EVM, spectrum ...


Effect of oversampling on Signal Band width

Started by Ali A Nasir in comp.dsp8 years ago 5 replies

Can anyone tell that what is the effect of doing oversampling before pulse shaping on the transmission bandwidth? My concern is that as books...

Can anyone tell that what is the effect of doing oversampling before pulse shaping on the transmission bandwidth? My concern is that as books describe that doing upsampling and then filtering results in reduction in the Bandwidth but at the same time if we view it from different angle, we are throwing more samples per second so so shouldn't Bandwidth also be increased ? Thanks in advance. ...


Oversampling for noise reduction

Started by stevepierson in comp.dsp10 years ago 11 replies

Hi, I've been reading quite a bit about oversampling and it's apparent use in noise reduction, but haven't been able to tie everything...

Hi, I've been reading quite a bit about oversampling and it's apparent use in noise reduction, but haven't been able to tie everything together. As I probably can't explain my exact question clearly, I'll give an example, I have a Analog Devices evaluation board with a 1MSPS A/D with CPU hooked up to a gryo. The gyro has a raw BW of 1000Hz, I have a single pole filter at 50Hz between it and ...


Effect of OverSampling

Started by pratik13 in comp.dsp11 years ago 8 replies

I'm new to DSP and also this group. My question is "what can be the negative effect of Oversamling in terms of Destortion in original signal?"....

I'm new to DSP and also this group. My question is "what can be the negative effect of Oversamling in terms of Destortion in original signal?". As in undersampling two spectrum are overlapped and we may not be able to get original signal.. is that any kind of effect in oversampling?


Effect of oversampling on SFDR

Started by SRB in comp.dsp4 years ago 21 replies

Hi All My question relates to the effect of oversampling on the SFDR obtained with an ADC. I understand that the SNR of an ADC, considered over...

Hi All My question relates to the effect of oversampling on the SFDR obtained with an ADC. I understand that the SNR of an ADC, considered over a certain bandwidth of interest (BW), can be increased relative to the overall SNR by sampling at a rate (Fs) such that Fs/2 > > BW, and that the resulting increase in SNR is 10log(Fs/2*BW). This has been clearly explained in the responses to a previous


Oversampling vs. nr. Bits

Started by galatisa in comp.dsp12 years ago 3 replies

Hi, I'm sampling a signal with a 35 MHz BW at a rate of 100Msa/s and 12 bit. The nature of the signal is something like 100ns Peaks at about 2/3...

Hi, I'm sampling a signal with a 35 MHz BW at a rate of 100Msa/s and 12 bit. The nature of the signal is something like 100ns Peaks at about 2/3 of peak value. I need the integration over each signal(100ns) but due to the sampling rate I only get at about 4-10 samples of every signal, a number which is not enough. So I thougth of oversampling but since the data stream is processed by a virte...


Using oversampling to enhance SAR ADC performance

Started by Myron Mychal in comp.dsp14 years ago 4 replies

I'm working with the new 56F630x series of Motorola DSP's (with an onboard 12-bit ADC). My application could make good use of 14-bit data, so I...

I'm working with the new 56F630x series of Motorola DSP's (with an onboard 12-bit ADC). My application could make good use of 14-bit data, so I planned on oversampling by a factor of 16 and filtering with decimation to get an extra 2 bits out of the ADC. I recently spoke with someone from Motorola who suggested that this might not work with their ADC because it doesn't ensure equal probab...


Zeropadding vs. Oversampling

Started by gabi in comp.dsp11 years ago 7 replies

Hi, I've got a fundamental question. I have a signal (impulse response of a room, computed from the original signal and the recorded signal)...

Hi, I've got a fundamental question. I have a signal (impulse response of a room, computed from the original signal and the recorded signal) and now I want to find out the maximum of that impulse response. This IR has to be interpolated somehow, right now it is done by oversampling, but I was wondering if there could be another possiblity like zeropadding. The question is now, what will be ...


Oversampling for discrete time input

Started by Richard_K in comp.dsp11 years ago 4 replies

Hi, May I know how to perform oversampling for discrete time input in MATLAB? Thanks

Hi, May I know how to perform oversampling for discrete time input in MATLAB? Thanks


oversampling in OFDM

Started by mishal81 in comp.dsp6 years ago 1 reply

Hi All,, Plz help me for ofdm simulation. I have tried to simulate ofdm signal with 64 subcarriers, with an oversampling of factor 4 in...

Hi All,, Plz help me for ofdm simulation. I have tried to simulate ofdm signal with 64 subcarriers, with an oversampling of factor 4 in frequency domain. Now I've got 256 QPSK symbols with zero paddings.I'm doing IFFT of 256 points. But I need to modulate my data on 64 subcarriers. then how would it be possible if i'm doing IFFT/FFT of 256 points. plz clarify me this thing, if i have zeronpadde...


Maximum useable oversampling rate10x analog signal bandwidth?

Started by steve in comp.dsp12 years ago 15 replies

Analog Devices comments on their web site that for oversampling to work the sample rate cannot be over 10 times the analog signal bandwidth....

Analog Devices comments on their web site that for oversampling to work the sample rate cannot be over 10 times the analog signal bandwidth. So this defines the upper bounds on how much you can reduce the noise floor of an analog signal. So I am thinking what magical about 10x, but I suppose they are implying that if you had a 100hz bandwidth limited signal and oversampled it 1024 times at 1G...