Comparison of common channel and alternative signaling technology for multichannel radio dispatch and telephone systems

To accomplish multichannel access on vehicular radio systems, it is necessary to provide a signaling system to initiate communications. This signaling function may be accomplished on a dedicated signaling channel or may be distributed over all of the communications channels. A summary of the considerations involved in specifying this system characteristic is presented. It is concluded that the dedicated signaling channel results in a fixed partition between signaling and talking capacity. If the loading of a common signaling channel would be sufficiently light so that it does not limit the talking capacity of the system, then probably the signaling function can also be distributed on the talking channels, still providing all necessary functions. With distributed signaling, the partitioning of capacity between signaling and talking can adapt to the traffic presented.