MQAM/CDMA for increased cellular capacity

Author

Gejji, Raghvendra R.

Author_Institution

Dept. of Electr. Eng., Western Michigan Univ., Kalamazoo, MI, USA

fYear

1993

fDate

18-20 May 1993

Firstpage

46

Lastpage

48

Abstract

The CDMA (code division multiple access) technique can provide efficient multiple access to a large number of users. CDMA as a multiple access method can be combined with any desired modulation technique. The author considers the result of combining CDMA access with a high-efficiency modulation technique, e.g., 256-QAM (quadrature amplitude modulation), and whether the bandwidth efficiency of high-level QAM can be used to overcome the bandwidth inefficiency of CDMA. A mathematical model is built to compare cellular capacity obtained with and without MQAM-CDMA use. It is seen that MQAM-CDMA leads to reduced capacity, indicating that the advantages of the two schemes are not enough to overcome each other´s disadvantages

Keywords

cellular radio; channel capacity; code division multiple access; quadrature amplitude modulation; 256-QAM; MQAM-CDMA; bandwidth efficiency; cellular capacity; code division multiple access; high-efficiency modulation; mathematical model; quadrature amplitude modulation; Amplitude modulation; Bandwidth; Error analysis; Forward error correction; Mathematical model; Multiaccess communication; Noise level; Quadrature amplitude modulation; Rayleigh channels; Signal to noise ratio;

fLanguage

English

Publisher

ieee

Conference_Titel

Vehicular Technology Conference, 1993., 43rd IEEE

Conference_Location

Secaucus, NJ

ISSN

1090-3038

Print_ISBN

0-7803-1267-8

Type

conf

DOI

10.1109/VETEC.1993.507007

Filename

507007