A combined OFDM-CsDMA approach to cellular mobile communications
Li Ping · IEEE Transactions on Communications · 1999
We present a combined orthogonal frequency-division multiplexing (OFDM) and code-division multiple-access cellular system. It is derived from the OFDM model by introducing an extra code-shift division multiple access layer. This mitigates intercell interference without affecting intracell orthogonality and such property can be maintained in multipath environments. The new scheme is suitable for both up and down links. It retains the low-receiver complexity property of the OFDM system.