A new multi-carrier CDMA/TDD transmission scheme based on cyclic extended spread code for 4th generation mobile communication system

This paper proposes a fiber-optic and OFDM radio based mobile advanced communication system; which is called the FORMATION system. In this system, all microcellular base stations are connected with a fiber-optic bus link by using an optical coupler; and each base station and control station have only an electrical to optic converter, an optic to electrical converter and an OFDM transmitter and receiver. To manage the frequency band efficiently in one cellular, we communicate with other users by using MC-CDMA/TDD (multi-carrier code division multiple access/time division duplex). Therefore we propose a new MC-CDMA/TDD system that is suitable for the FORMATION system. The proposed MC-CDMA/TDD system uses cyclic extended code division multiplex and it is very easy to synchronize the code and FFT start point at the OFDM receiver. This paper explains the basic concept of the FORMATION system and the new MC-CDMA/TDD system, and evaluates the basic BER performance of proposed MC-CDMA system.