Cellular radio communications system.

摘要

In a cellular radio communications system: (i) at least one signal comprising control channel information is broadcast on a carrier to subscribers within the cellular radio communications system; (ii) the said carrier is divided into TDMA frames, each TDMA frame having a frame number (N); (iii) the system is adapted to store at least two sets (S0-S2) of pre-determined frequencies (fi), the said carrier being broadcast at any particular time on a frequency taken from a selected one of the said sets (S0-S2) of pre-determined frequencies (fi); (iv) the system is adapted to chose the said selected one of the said sets of pre-determined frequencies (fi) in dependence on the frame number (N) of the TDMA frame being broadcast at the said time. The invention allows the radio system to employ both frequency hopping and multi-slot transmission, for example in an EDGE compact GSM system.