WiMAX throughput calculations
Hi all,
I am trying to calculate the PHY data rate of WiMAX (OFDMA-IEEE
208.16e) for different BW values (3.5,7,8.75,10,and 20MHz).
The WiMAX forum document (Mobile WiMAX Part I: A Technical Overview
and Performance Evaluation) gives these rates for DL PUSC for 5MHz,
and 10 MHz..
My calculations don't match with theirs !
Here you are how I proceed:
The PHY DATA rate = The number of Used Data Subcarriers * (Number of
bits /subcarrier) / Ts
where :
-The number of Used Data Subcarriers = 360 for DL PUSC (given in the
standard)
- Number of bits /subcarrier depends on the MCS used ( i.e. 2 *0.5 for
QPSK-1/2)
-Ts : is the OFDM symbol duration (= Tb Tg)
-Tb = 1/delta_f
-Tg = Tb/8
-delta_f depends on the FFT size.
all these relations are given in the standard.
Am I proceeding in the right way ??
I'm also wondering why the Frame_Duration (i.e. 5ms is not used in my
calculations) !?
Does that mean the throughput doesn't depend on the Frame_Duration ?!
(a bit strange)
Any comments would be really appreciated..
Thanks
Best Regards
Hany Kamal
date: Tue, 27 May 2008 10:46:49 -0700 (PDT)
author: Hany Kamal
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