stds-80220-requirements: spectral efficiency
In order to help understand where the existing mobile systems stand in terms of spectral efficiency, I have attached below a paper containing description and performance of such a system (HSDPA). This is in response to discussion on today's CG call regarding the spectral efficiency target in the requirements document. Understanding the spectral efficiency of exiting mobile systems and the PAR statement below can help on converging a target spectral efficiency number for the 802.20 systems.
"...and targets spectral efficiencies, sustained user data rates and numbers of active users that are all significantly higher than achieved by existing mobile systems."
In order to calculate the spectral efficiency (b/s/Hz/sector), the service throughput numbers given in Table 5, 6 and 7 need to be divided by the 5MHz HSDPA carrier bandwidth. Note that these numbers should be seen in the light of the traffic model, channel models, scheduling algorithm and other system assumptions provided in the paper. For example, only 62.5% CDMA code space (10 orthogonal codes out of 16 codes) is used for HSDPA in the simulations. With full code usage, the actual spectral efficiency can be higher.
As a co-author of the attached paper, I would be glad to provide answers to any questions that the requirements CG members may have.
Thanks,
Farooq Khan, Ph.D.
Bell Labs - Lucent Technologies
Whippany, NJ
hsdpa-bltj.zip