Digital short-range radio

Trying to accommodate an ever-increasing number of private mobile-radio (PMR) users within the current PMR frequency bands is resulting in serious congestion and a decline in grade of service. In response to this situation, PMR licensing authorities are increasingly encouraging operators to use trunked PMR schemes. The author shows that, by pooling channels (so that users have potential access to a larger number of channels) trunking schemes can make better use of the channels available and improve the grade of service to users. Such a system is possible using digital short-range radio (DSRR) which is a high quality cost-effective trunked PMR scheme that is easy to use, simple to license the secure in operation. It should prove highly appealing to users of existing private nontrunked schemes, as well as attract a whole new class of users for whom all existing forms of PMR appear excessively complicated and expensive