BPSK demodulation

Started by trung86 in comp.dsp11 years ago 2 replies

Hi all!! I have implemented BPSK modulation with DSK 6713.I'm writting a program to implement BPSK modulation and demodulation on the same Kit...

Hi all!! I have implemented BPSK modulation with DSK 6713.I'm writting a program to implement BPSK modulation and demodulation on the same Kit DSK 6713, but it doesn't run. Can we implement BPSK modulation and demodulatio on the same Kit DSP?. I wil post my source code later! By the way! I also have a project about QPSK demodulation, but when I recover carrier wave, I only recover sin wave(in_pha...


xr2211 & non coherent fsk demodulation

Started by josedebrest in comp.dsp13 years ago 1 reply

Hello, I am using the XR 2211 to demodulate a non coherent fsk signal. It works but I would like to know how to evaluate the theoritical...

Hello, I am using the XR 2211 to demodulate a non coherent fsk signal. It works but I would like to know how to evaluate the theoritical BER performance of this demodulation. But all the non coherent fsk receivers that are mentionned on the web dont use a pll ... any idea ? thank you very much jean michel


AM demodulation using I and Q

Started by lightmetal in comp.dsp17 years ago 27 replies

I started a thread re: AM demodulation using I and Q a few weeks ago and I am still having a problem. According to Frerking, AM should...

I started a thread re: AM demodulation using I and Q a few weeks ago and I am still having a problem. According to Frerking, AM should be A=sqrt(i^2+q^2). This works if I tune off the AM zero beat frequency by 1/2 the low pass filter bandwidth. I don't understand this problem. A little more detail: I am using a pair of mixers fed with a sin/cos local osc. to generate I/Q at baseband....


Sample rate and baud rate issue

Started by in comp.dsp14 years ago 3 replies

I'm working on FSK demodulator with the TMS320C6711 DSK. I've done this demodulation with the method where the signal and its delayed version...

I'm working on FSK demodulator with the TMS320C6711 DSK. I've done this demodulation with the method where the signal and its delayed version are multiplied together and then low-pass filtered. But this demodulation technic is only working if the sample rate is an integer multiple of the baud rate. Does someone know a technic or an algorithm which allow a demodulation of a 300 baud rate signal wit...


SDR - Demodulation of DVB-C

Started by Vieriksson in comp.dsp7 years ago 11 replies

Hi, I am having some issues with the IQ-demodulation of a DVB-C signal. Even though it works fine on synthesized data, I can't get the timing...

Hi, I am having some issues with the IQ-demodulation of a DVB-C signal. Even though it works fine on synthesized data, I can't get the timing recovery to work on real data. Can anybody tell me what I am doing wrong or where the problem is most likely to occur? Transmitter: Transmits symbols at 4.5 Msymbols/s with a certain carrier frequency and modulates it with QAM-16. Receiver: ...


SNR DSSS WCDMA

Started by Anonymous in comp.dsp14 years ago

hi everybody, Did you know if the SNR (to compute the BER vs SNr) is compute after or before the complex demodulation DQPSK (Dot and Cross)...

hi everybody, Did you know if the SNR (to compute the BER vs SNr) is compute after or before the complex demodulation DQPSK (Dot and Cross) ? After the demodulation, we integrate the signal (Dot and Cross) and then we make the symbol decision ? Thanks


FM Demodulation problem (Lyons Ch. 13.22)

Started by Rune Allnor in comp.dsp16 years ago 2 replies

Hi all. I've tried to implement an FM demodulation scheme, as suggested by Rick in ch. 13.22 of his 2nd edition (MATLAB code attached at the...

Hi all. I've tried to implement an FM demodulation scheme, as suggested by Rick in ch. 13.22 of his 2nd edition (MATLAB code attached at the end of the post). I have based my approach on Rick's eq. 13-117, but I can't get it to work: - When I don't include the denominator i(n)^2+q(n)^2, I get an instantaneous phase estimate that's close to the "correct" one, but with a sign ...


Fax signals demodulation

Started by MMHafezi in comp.dsp15 years ago 1 reply

Dear friends, I'm trying to develope a PC application to receive and send faxes using ula samples of telephone channel. Can any one help me...

Dear friends, I'm trying to develope a PC application to receive and send faxes using ula samples of telephone channel. Can any one help me to find some usefule guides, trial applications, sources, ... on demodulation of V.21, V.27ter and V.29 signals? Thanks in Advance This message was sent using the Comp.DSP web interface on www.DSPRelated.com


V.34 demodulation

Started by Vito in comp.dsp12 years ago 8 replies

Hallo everybody, I am just starting a C++ project about V.34 fax demodulation and decoding on PC. In all my previous DSP projects I had an...

Hallo everybody, I am just starting a C++ project about V.34 fax demodulation and decoding on PC. In all my previous DSP projects I had an analog front-end which provided me the baseband samples, or I could recovery them in some other tricky way (e.g. FFT in narrow-band OFDM systems). Anyway, all my processing ever took place at baseband. In this case, on the contrary, my input is a digit...


software demoduation

Started by nina121 in comp.dsp12 years ago 14 replies

Hi all, I am new to much of this, so thanks in advance for your patience. Where can you find C++ (or C or C#) source code for ASK, FSK, PSK,...

Hi all, I am new to much of this, so thanks in advance for your patience. Where can you find C++ (or C or C#) source code for ASK, FSK, PSK, QAM, PPM, and BPSK demodulation schemes? I have a feeling that if they exist they won't be free, but that's a problem for another day...Matlab and LabView have great modulation/demodulation toolkits, but we are looking for source code. Thanks again--Ni...


Digital FM demodulation

Started by Anonymous in comp.dsp14 years ago 4 replies

hello, I'm designing a receiver for FM demodulation and I have a little problem with the filters of the downconverter. Here's my...

hello, I'm designing a receiver for FM demodulation and I have a little problem with the filters of the downconverter. Here's my specifications : FM carrier 10,7 MHz, 20 kHz deviation. I send to the modulator a 19.2 kHz sinus signal. At the receiver, I first band-pass filter the carrier : center to 10,7 MHz with 80 kHz bandwidth. Then I undersample at 4 MS/s : so I have got a first ...


how much dopler effect are DVB-T receivers on the market conquer?

Started by daor in comp.dsp14 years ago 3 replies

how many people are here designing the DVB-T demodulation ASIC? I am very interested in the performance of DVB-T receivers on the market or to...

how many people are here designing the DVB-T demodulation ASIC? I am very interested in the performance of DVB-T receivers on the market or to be on the market,and i would like to discuss the OFDM demodulation technology here with you. 3x!


how much doppler effect are DVB-T receivers on the market able to conquer?

Started by daor in comp.dsp14 years ago

how many people are here designing the DVB-T demodulation ASIC? I am very interested in the performance of DVB-T receivers on the market or to...

how many people are here designing the DVB-T demodulation ASIC? I am very interested in the performance of DVB-T receivers on the market or to be on the market,and i would like to discuss the OFDM demodulation technology here with you.


Blind demodulation of things like V.34

Started by Steve Underwood in comp.dsp15 years ago 2 replies

Hi all, I have never implemented blind demodulation of QAM, and seen all the problems first hand. However, the material I have seen on the...

Hi all, I have never implemented blind demodulation of QAM, and seen all the problems first hand. However, the material I have seen on the subject is all based on despinning the constellation by looking for the corners of a square (or squarish) array sticking out. In schemes like V.34 where the constellation has been completely rounded, to avoid high energy states, are there any pract...


AM digital demodulation methods

Started by gretzteam in comp.dsp10 years ago 59 replies

Hi, I'm having trouble understanding the similarities/differences/advantages of various AM digital demodulation methods, which makes me incapable...

Hi, I'm having trouble understanding the similarities/differences/advantages of various AM digital demodulation methods, which makes me incapable of deciding what to use. I would like to go throug a few methods here and here your thoughts. First, I assume the common goal of all those techniques is to shift the carrier back down to DC and there are a few ways to do this that have different beh...


FSK Modulation/ demodulation

Started by Somia in comp.dsp15 years ago 2 replies

Hi I have to communicate with telephone which is sending us data that is in voice band and FSK modulated. I dont have an fsk modem so i am...

Hi I have to communicate with telephone which is sending us data that is in voice band and FSK modulated. I dont have an fsk modem so i am trying to do FSK demodulation in software. I'll record that data in a wave file and then analyise it. i dont have any signal processing background and i am stuck in this problem. please help according to the standard: Mark is represented by 1300Hz, ...


FSK Modulation/ demodulation

Started by Somia in comp.dsp15 years ago 1 reply

Hi I have to communicate with telephone which is sending us data that is in voice band and FSK modulated. I dont have an fsk modem so i am...

Hi I have to communicate with telephone which is sending us data that is in voice band and FSK modulated. I dont have an fsk modem so i am trying to do FSK demodulation in software. I'll record that data in a wave file and then analyise it. i dont have any signal processing background and i am stuck in this problem. please help according to the standard: Mark is represented by 1300Hz, ...


msk demodulation

Started by harsh17 in comp.dsp15 years ago 5 replies

Hi evrybdy, I am new to this grp.I am working on a project involving demodulation of msk signals.The transmitter has been...

Hi evrybdy, I am new to this grp.I am working on a project involving demodulation of msk signals.The transmitter has been implemented using a AD9851 DDS chip.The transmitter switches between 16MHz and 24MHz depending on the incoming bits.At the receiver,I am using AD6620 to downconvert the signal to baseband and then AD6640 A to D converter digitizes the signal.I intend to do the bas...


Coherent vs Noncoherent GFSK Demodulation

Started by john in comp.dsp15 years ago 2 replies

Hi, I've been working on demodulation of low-deviation GFSK signals similar to Bluetooth, with h=0.3 and BT=0.5. I have two simulations, one...

Hi, I've been working on demodulation of low-deviation GFSK signals similar to Bluetooth, with h=0.3 and BT=0.5. I have two simulations, one using a discriminator plus integrate and dump, and another with a second order PLL. I am computing BER vs Eb/No for each case. In the PLL case, I expect to see a few dB of improvement compared to the discriminator, but I'm not getting that. I'm either...


OFDM, symbol/phase synchronization, demodulation

Started by Sebastian in comp.dsp9 years ago 12 replies

Hello, I recently found myself interested in digital modulation techniques. For a hobby project I plan to implement modulation and...

Hello, I recently found myself interested in digital modulation techniques. For a hobby project I plan to implement modulation and demodulation so I can later test it using soundcards for transmitting little text messages via sound between neighbouring laptops. The main goal is to learn something and have fun -- not to build something useful. I'm sure some of you could provide valuable sug...