FFT processor for microphone signals below 150Hz

[Kinshoro]

Re: FFT processor

can anyone suggest me a good FFT processor for fast applications and low power consumption????

Added after 1 hours 5 minutes:

I need an FFT processor to get the FFT from a microphone signal... is it possible to get a 3V power supply with 24 bit resolution FFT processor???? Is it cheap because I dont need it for a very high functional application... After converting the signal to FFT I just need to find a means to calculate the peak amplitude and its corresponding frequency from the FFT. Can anyone suggest me something???

 

[GSM Man]

Re: FFT processor

"Fast" and "Low Power" are all relative terms...they mean differant things to differant people. Microchip has many "fast, low power" micro processors that may meet your requirements. They also have free DSP librabires (including FFT) and demo boards. Suggest you start by looking at their web site http://search.microchip.com/searchapp/searchhome.aspx?id=2&q=fft

 

[Kinshoro]

Can you tell me the ideal number of points on an FFT for a good resolution but fast application of conversion from the signal to the FFT and also the sampling Frequency that is ideal for a microphone signal that has a time period of 7milliseconds or even lesser. What would be the ideal bit resolution for such an application????? The microphone signal goes from 0 to a maximum of 150Hz..............

Added after 2 hours 1 minutes:

MODEL:C8051F930DK
COMPANY:SILICON LABS
TYPE: 8051 MICROCONTROLLER
Would this be ok for the purpose of my application... It has True 10-bit 300 ksps 23-channel single-ended ADC with analog multiplexer and 24 or 16 Port I/O (5 V tolerant)...............

 

[philoman]

According to Shannon&Naquist sampling theroy, the sampling freq should be at least twice of the bandwidth, which is 300Ksps in your case.
The freq resolution is calculated as Fs/N, in which Fs is the sampling freq and N is the number of the FFT points.

 

[FvM]

twice of the bandwidth, which is 300Ksps in your case

The frequency range has been said to be 150 Hz. If so, DSP computing power isn't an issue at all. In any case, nothing
has been said about intended FFT frequency resolution respectively block length and repetition rate. Without this information,
you can't decide about the processor requirements. Even a 8 bit micro would be able to compute the FFT (possibly with some
external RAM).

 

[mailoan1909]

can anyone help me how to apply unwindowed fft to decompose wide-band signal to narrow-band signal?