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Undersampling

Started by meht...@gmail.com January 28, 2009
I am amature to Software Defined Radios.
I am facing a problem regarding the selection of sampling frequency of ADC.
How to decide the sampling frequency so the carriers of different channels do not overlap.
I want to tune the receivers to different FM channels.

These are the different frequencies to which I want to tune the receiver.

Radio Mirchi 98.3 FM
Radio City 91.1 FM
Radio One 94.3 FM
S FM 93.5 FM
Vividh Bharati 101.0 FM
Radio FTII 90.4 FM
Big FM 92.7 FM

Thank You
Nupur
since
the highest frequency is 101.0 MHz of vividh bharati, u need to sample at
atleast 202MHz as per Nyquist criteria. With this sampling rate, all ur
signals can be sampled. you need to have a FIR filter to separate out
different channels - considering their bandwidth and central frequency.
regards,
vikas

Undersampling
I am
amature to Software Defined Radios.
I am facing a problem regarding the selection of sampling frequency of ADC.
How to decide the sampling frequency so the carriers of different channels
do not overlap.
I want to tune the receivers to different FM channels.

These are the different frequencies to which I want to tune the receiver.

Radio Mirchi 98.3 FM
Radio City 91.1 FM
Radio One 94.3 FM
S FM 93.5 FM
Vividh Bharati 101.0 FM
Radio FTII 90.4 FM
Big FM 92.7 FM
Thank You
Nupur
Dear Vikas,

To the best of my knowledge it will be never like that.,
what happens if there is a station which transmits over 101.0 Mhz,
like Fever FM which transmits at 104.0Mhz(If am not wrong)

as per the FM Radio standard all the frequencies are
bought down to one IF(Intermediate Freq) of 10.7Mhz,
and you need to sample this IF atleast twice as per
the Nyquest Theory....

Best Regards
KalyanSuman KV

----- Original Message -----
From: Vikas Akalwadi
To: f...
Sent: Thursday, January 29, 2009 4:00 PM
Subject: [fpgadsp] Re:Undersampling
since
the highest frequency is 101.0 MHz of vividh bharati, u need to sample at
atleast 202MHz as per Nyquist criteria. With this sampling rate, all ur
signals can be sampled. you need to have a FIR filter to separate out
different channels - considering their bandwidth and central frequency.
regards,
vikas

Undersampling
I am
amature to Software Defined Radios.
I am facing a problem regarding the selection of sampling frequency of ADC.
How to decide the sampling frequency so the carriers of different channels
do not overlap.
I want to tune the receivers to different FM channels.

These are the different frequencies to which I want to tune the receiver.

Radio Mirchi 98.3 FM
Radio City 91.1 FM
Radio One 94.3 FM
S FM 93.5 FM
Vividh Bharati 101.0 FM
Radio FTII 90.4 FM
Big FM 92.7 FM

Thank You
Nupur