Assessment of high bit rate mobile OFDM systems using the codit channel model

Broadband transmission at high data rates with high mobility speeds over wireless propagation channels is subject to both time dispersion caused by the multipath channel and frequency dispersion or Doppler Spread. Orthogonal Frequency Division Multiplexing (OFDM), with its variants, represents a candidate modulation technique for the air interface of next generation mobile communication systems. The main objective of this paper is to assess the performance of OFDM based cellular mobile communication systems under realistic conditions using a time varying channel model with a range of indoor and outdoor channel types. Performance is evaluated by detailed simulation using the CODIT channel model that was refined and validated using measurements made within the RACE project in the UK. The paper presents a detailed evaluation of the BER, PSD for an OFDM system suitably dimensioned for the mobile radio channel.