Re: [Discuss-gnuradio] Processing multiple signals off single source block

[Johnathan Corgan]

On Thu, Aug 22, 2013 at 3:24 AM, Marcus Müller <address@hidden> wrote:

 

On 08/21/2013 08:15 PM, Luke B wrote:

 - What is the best approach performance wise for selecting multiple ~15khz channels from a 2mhz+ source block? Is it using a Xlating FIR Filter with a low-pass? Is it more efficient to use a SIN Sig source & Multiply Block with a low-pass FIR Filter? Is there a better way to extract a filter?

Xlating FIRs just generate the sin internally and apply it themselves; they are mathematically equivalent to shifting your signal and filtering it afterwards.

FYI, the Xlating FIR filter uses a rotating complex unit vector (with periodic renormalization) to accomplish the frequency shift, so this is much more computationally efficient than the signal source block.

Also, it may be an option to use the polyphase channelizer block.

-- 
Johnathan Corgan
Corgan Labs - SDR Training and Development Services
http://corganlabs.com