A multi-channel communication system is disclosed in which a base station is in communication with a plurality of user terminals. To enable the user terminals to perform equalisation on signals sent to the base station, the base station transmits periodic multi-carrier reference bursts on a channel assigned to the user terminals for use in transmission of signals to the base station. The user terminal can analyse the reference signals that it receives from the base station and from that analysis deduce the condition of the channel and adjust the signals that it transmits accordingly. The system may be embodied in a multiple access orthogonal frequency division multiplexing arrangement, for example, being in accordance with an ETSI EN300xxx standard, in which data is digitally encoded in RF signals. It may also be embodied in Voice over IP communication.