How do equalizers work?

[wee]

Hi all,

I would like to know more about the functionality of Equalizers? For example in a GSM Modulation and De-modulation stage.

The signal is modulated with GMSK scheme and demodulated at the receiver (assuming synchronized network) and then passed through a bandpass filter same as the transmitter end. Then the original signal is extracted (including some distortions). We will require the use of Equalizers to further improve the decoding using Max. Likelihood decoding technique.

I have chosen a good G but when i plotted the BER, the BER does not decline as Eb/No increases. I am not sure what went wrong.

Please advice.

Thank you.

 

[brmadhukar]

Re: How Equalizers work?

Hi,

I guess uyou are simulating on Matlab.

You can disable the timing errors and check if the equalizer is converging. Basically the coefficients should stabilize.

BR
Madhukar

 

[wee]

Re: How Equalizers work?

Hi,

I guess uyou are simulating on Matlab.

You can disable the timing errors and check if the equalizer is converging. Basically the coefficients should stabilize.

BR
Madhukar

Hi brmadhukar,

Yes. The simulation is done in MatLab.

With regards to the timing errors, how do i disable it? Shall i assume total synchronization in the multipath signals by aligning all to zero phase?

Pleae advice.

Thank you.

Regards,
Wee