Can I use c6711 to impletment digital down-converter ?

[vonzhaoqun]

digital down converter

can i use c6711 to impletment digital down-converter ? my input signal is about 330KHZ(sonar).need any information about this.thank you.

 

[Usman Hai]

Re: digital down-converter

why not u r using FPGA for DDC.
Is it much better approach.

USMAN HAI

 

[panda]

digital down-converter

is down-converter the same as down-sampling?

 

[rfsnack]

digital down-converter

no,

down converter is mostly like mixer in analog circuits. after down converter, the signal central frequency has been changed ( from a higher frequency to a lower frequency).

down sampling is realized by decimation filter. what is changed in this process is signal sampling rate.

 

[ramesh]

Re: digital down-converter

is down-converter the same as down-sampling?

They are not same.
Down-converter refers to shifting the modulated signals spectrum to a lower centre frequency which depends on the a local carrier, the one of the input at mixer. This process doesn't change the spectral bandwidth.

Down-sampling refers to the decreasing the sampling rate of a signal. In this process the original signal's spectral bandwith will be reduced to avoid spectral aliasing and it depends on the decimation rate.

 

[Usman Hai]

Re: digital down-converter

Down converters basically converts the signal into IF and then it goes to demodulator for further processing.

While in downsampling u reduces the sample rates and with this the sampling frequency decreases and to avoid alliasing u have to reduce the frequency of the signal (Nyquist rate).

USMAN HAI
PAKISTAN

 

[Usman Hai]

Re: digital down-converter

I m also working on DDC.

can any one guide me shud i use CIC decimation filter or FIR decimation filter. whose response would be better.

thanks

USMAN HAI