COMMUNICATION SYSTEM, RADIO UNIT AND METHOD OF PERFORMING A HANDOVER

摘要

A mobile station and its serving base transceiver station both have means to generate cell parameter information of a neighbouring cell to facilitate communication handover to the neighbouring cell, without the mobile station accessing or receiving information from the neighbouring cell providing said neighbouring cell parameter information. This avoids the need for background scanning of candidate neighbour cells by the mobile to determine the required synchronisation offset and operating parameters, such as the colour code (determines scrambling and frequency re-use pattern), maximum mobile transmit power or minimum receiver access level. Preferably in a shared Terrestrial Trunked Radio (TETRA) system only the colour code is required and the mobile and base station may use a linear feedback shift register (LFSR) to generate a pseudo-random sequence used to set the appropriate colour code. The generation may involve use of the neighbour cell id and location area (LA), periodically transmitted to the mobile by the serving base station. Facilitates seamless handover and reduces dropped calls or breaks in communications due to handovers.