FSK Modulation/ demodulation

Started by Somia in comp.dsp12 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.dsp12 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, ...


FSK modulated wave file

Started by pal.debabrata123 in comp.dsp10 years ago 29 replies

Hey guys, Though my problem is do a FSK modulation os an ascii string and send it to telephone between "init ring" and "full ring" , I don't...

Hey guys, Though my problem is do a FSK modulation os an ascii string and send it to telephone between "init ring" and "full ring" , I don't know how to test. Is there a software FSK demodulator free somewhere? Can I get some standard FSK modulated file to test the decoder? So that I am test my code in that environment..


PSK instead FSK?

Started by maluenda in comp.dsp12 years ago 1 reply
FSK

Hi, I just started up some reading on Digital Communications. I need some information about PSK vs FSK for use in DSP. Can anyone explain in...

Hi, I just started up some reading on Digital Communications. I need some information about PSK vs FSK for use in DSP. Can anyone explain in few words the advantages of using PSK instead FSK? Will appreciate any help in this regard. Thanks


FSK Demodulation (help urgently needed)

Started by mudassir84 in comp.dsp11 years ago

Hi I am trying to Extract Caller ID from FSK v.23 Encoded CLI Packet which has been stored in audio format in pc. To demdulate FSK i am using...

Hi I am trying to Extract Caller ID from FSK v.23 Encoded CLI Packet which has been stored in audio format in pc. To demdulate FSK i am using two Bandpass Filters centered at Mark and Space Frequency. According to FSK V.23 1300 hz is frequency for mark(1) 2100 hz is frequency for spcae(0) 1200 is baud rate my sample rate is 8000/s i have 1/1200=833 us to check for the new arrival. In 833 ...


xr2211 & non coherent fsk demodulation

Started by josedebrest in comp.dsp10 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


software for generating FSK modulated signals

Started by Somia in comp.dsp12 years ago 2 replies
FSK

hi I have to generate signals with data encoded in them using FSK, 1300Hz for mark and 2100Hz for space with a baud rate of 1200. i dont have...

hi I have to generate signals with data encoded in them using FSK, 1300Hz for mark and 2100Hz for space with a baud rate of 1200. i dont have an FSK modulator so is there any software that could do this over voice modem ? i dont have any backgound of DSP so i would really be thankful for you help or any other relavent information. Somia


Optimal digital FSK demodulator

Started by mf in comp.dsp8 years ago

Hi There, I was wondering if someone could help to define a good choice for digital FSK demodulation method? I need to demodulate a coherent...

Hi There, I was wondering if someone could help to define a good choice for digital FSK demodulation method? I need to demodulate a coherent FSK signal where fc=135kHz and mark and space separation is 10kHz. The detector must be able to work in a somewhat noisy environment but operate at (near) real-time. So a good trade-off between speed and accuracy as well as complexity since i'm only a und...


Optimal digital FSK demodulator

Started by mf in comp.dsp8 years ago 9 replies

Hi There, I was wondering if someone could help to define a good choice for digital FSK demodulation method? I need to demodulate a coherent...

Hi There, I was wondering if someone could help to define a good choice for digital FSK demodulation method? I need to demodulate a coherent FSK signal where fc=135kHz and mark and space separation is 10kHz. The detector must be able to work in a somewhat noisy environment but operate at (near) real-time. So a good trade-off between speed and accuracy as well as complexity since i'm only a und...


Equalizers for FSK systems

Started by Dan25 in comp.dsp3 years ago 4 replies

Hi All, I'm looking at FSK modulation in practical multi-path channels. What type of equalizers are suitable for FSK ? What type of equalizers...

Hi All, I'm looking at FSK modulation in practical multi-path channels. What type of equalizers are suitable for FSK ? What type of equalizers are appropriate for other non-coherent modulation schemes ? Highly appreciate if you could provide any relevant paper or a book. Thanks in advance. Dan _____________________________ Posted through www.DSPRelated.com


Is frequency multipliers suitable for boradband FSK?

Started by isgone in comp.dsp10 years ago 2 replies
FSK

there are many applications use frequency multipliers to improve the deviation of narrowband FSK . i wonder is it suitable for boradband FSK? For...

there are many applications use frequency multipliers to improve the deviation of narrowband FSK . i wonder is it suitable for boradband FSK? For example,the input signal should be 4FSK,and the frequencys is 67MHz/69MHz/71MHz/73MHz,the symbol rate is 10M .


Who made the comment about modems and FSK signals?

Started by Brian Reinhold in comp.dsp14 years ago 13 replies
FSK

I think some respondant named 'v' made a remark in response to a post I made last week regarding FSK decoding and filtering, but the post has...

I think some respondant named 'v' made a remark in response to a post I made last week regarding FSK decoding and filtering, but the post has been removed. The remark concerned the special processes that have to be done detecting FSK tones that are very short in the sense that the number of periods per pulse is barely more than one. I would like to get some more info! I have exactly that ...


Few taps Filters for FSK?

Started by Brian Reinhold in comp.dsp14 years ago 31 replies

Does anyone have any suggestions for an IIR or FIR band pass filter that will isolate the two tones of an FSK signal which an integrate and...

Does anyone have any suggestions for an IIR or FIR band pass filter that will isolate the two tones of an FSK signal which an integrate and dump scheme can then be applied to? I need to minimize the delay since this FSK signal comes from scanned radio frequencies. I need to detect the signal fast enough so the scanning can be stopped. The more taps, the greater the delay and the slower the...


FSK modulation problem....

Started by opamp in comp.dsp12 years ago 5 replies

Hi, I want to make fsk modulation. For example my baseband signal is "1010001110". Ones are represent by 2200 hz and zeroes are by 1100 hz. Now I...

Hi, I want to make fsk modulation. For example my baseband signal is "1010001110". Ones are represent by 2200 hz and zeroes are by 1100 hz. Now I know that for generating a fsk signal, I have to generate a signal that shows ones(as callded s1) and another one that shows zeros(as called s0). And when "1" comes, it has to be shown in s1; and when "0" comes, it has to be shown in s0; WHILE it is sho...


FSK demod: what filter I'm using?

Started by Andrea Baldoni in comp.dsp11 years ago 4 replies

Hello. I'm a newbie of DSP and I have just wrote the software in C for creating a FSK modulation (phase coherent, using a soft DDS) and...

Hello. I'm a newbie of DSP and I have just wrote the software in C for creating a FSK modulation (phase coherent, using a soft DDS) and demodulate it. Actually, I'm using the V.23 modem standard as a start point, so I have generated a 1300/2100Hz FSK with a bit rate of 1200BPS and sampling rate of 8KHz, wrote it to a file and fed to the demodulator. The demodulator is composed by two digital...


Receiving symbols using non-coherent M-FSK

Started by Anonymous in comp.dsp10 years ago 3 replies

Hi There, How does the demodulator of a non-coherent M-FSK system correctly time the "reading" of the symbols? In the book on Digital Comms...

Hi There, How does the demodulator of a non-coherent M-FSK system correctly time the "reading" of the symbols? In the book on Digital Comms by Proakis, it is mentioned that a bank of 2M correlators can be used. In the book there is also a model for non-coherent M-FSK in an AWGN environment. I have used the model to create a matrix of metrics and done the decoding/demodulation from there....


FEC for Burst FSK

Started by mite_learner in comp.dsp2 years ago 15 replies
FSK

Hi all, I started working on FEC for burst FSK system over multipath channel. I want to ask the community here about what type of FEC would be...

Hi all, I started working on FEC for burst FSK system over multipath channel. I want to ask the community here about what type of FEC would be best for such system. Which type of FEC is being used in existing FSK systems? Any pointers to literature and implementation work would be welcomed. -- Sam --------------------------------------- Posted through http://www.DSPRelated.com


Definition of BT in an FSK system

Started by Steve Pope in comp.dsp7 years ago 3 replies
FSK

BT denotes the product of the 3 dB bandwidth of the shaping pulse in an FSK system and the symbol time. My question has to do with the...

BT denotes the product of the 3 dB bandwidth of the shaping pulse in an FSK system and the symbol time. My question has to do with the conventional definition of B. My first thought was to use the 3 dB bandwidth of a bandpass function obtained by translating the baseband pulse up to the FSK center frequency; or equivalently, twice the bandwidth (from 0 Hz to the 3 dB point) of the pulse ...


FSK encoding: alternatives to Manchester and NRZ

Started by howy in comp.dsp11 years ago 15 replies
FSK

Hi all, I noticed a lot of FM related questions this month, so here is another one... I am transmitting FSK using a MICRF505 transceiver...

Hi all, I noticed a lot of FM related questions this month, so here is another one... I am transmitting FSK using a MICRF505 transceiver chip. The FSK modulator in this chip requires a bit encoding scheme to reduce the DC content of the bit stream to a manageable level. I am struggling with the extra bit rate needed in order to meet this requirement. I figure if I have to increase my b...


Definition of modulation index for shaped FSK

Started by Steve Pope in comp.dsp7 years ago 2 replies

I have a pretty elementary question. For an unshaped, 2-FSK signal, the modulation index h is defined as the ratio of the difference between...

I have a pretty elementary question. For an unshaped, 2-FSK signal, the modulation index h is defined as the ratio of the difference between the two tone frequencies to the symbol rate. For shaped 2-FSK, how is h usually defined? I can think of a few possibilities: (1) Base it on the peak frequency excursion exhibited by one isolated symbol, ignoring ISI from other nearby symbols. ...