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From: united on 7 Nov 2005 08:25
Hi there,

I am currently working on a GMSK Simulation whereby i will need to
simulate the raw binary bits -> NRZ -> Convolve NRZ with Gaussian Pulse ->
(I+Q)*modulator -> GMSK Modulation.

However, i am stuck in the integration of the NRZ and convolution of NRZ
and Gaussian Pulse. Please kindly advice.

Regards,
Wee


From: cb135 on 7 Nov 2005 09:38
GMSK is a phase modulation. You need to proceed as follows. Generate
your NRZ (PAM) symbols, convolve the PAM symbols with the Gaussian
pulse (you can find the definition of the Gaussian pulse in any digital
communications book. Proakis 4th ed definitely has it.).

Now express the convolved sequence as a phase rotation in radians
(2*pi*h) and then integrate from -infnty -> t (this is performed as a
cummulative sum of the phase angle (phi)) and raise to the exp(j*phi)
to give you your complex (I&Q) -> GMSK modulation.

col


united wrote:
> Hi there,
>
> I am currently working on a GMSK Simulation whereby i will need to
> simulate the raw binary bits -> NRZ -> Convolve NRZ with Gaussian Pulse ->
> (I+Q)*modulator -> GMSK Modulation.
>
> However, i am stuck in the integration of the NRZ and convolution of NRZ
> and Gaussian Pulse. Please kindly advice.
>
> Regards,
> Wee

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