Abstract:
Status and alerting signals are distributed in a TDM communication system in a split-up form in broadcasting mode: the cadencing information of all status/alerting signals is distributed in word format on an existing signaling channel, each bit of such a word representing the scan value of a different status/alerting signal at a given moment. The basic tone common to all status/alerting signals may be distributed in coded form on a special or a common channel like voice signals. Any terminal instructed to do so will regenerate any required tone signal for itself.
Abstract:
A closed loop communication system in which the terminals are grouped into priority classes. Any terminal can seize a free channel if certain priority conditions exist. A channel (frame) is always preceded by a header comprising a priority request field and a priority grant field. The request field has n bits assigned to the n priority classes; a terminal requiring service sets that bit to "1" which corresponds to its class. Thus, the controller receives a compiled overall request and inserts, for the next cycle, into the grant field an indication as to which priority class or classes are now allowed access to the channel. This is accomplished by shifting the contents of the request field to the grant field. A terminal can only seize the channel if its priority class is allowed for that cycle by the grant field, and if the channel is still free.
Abstract:
Status and alerting signals are distributed in a TDM communication system in a split-up form in broadcasting mode: the cadencing information of all status/alerting signals is distributed in word format on an existing signaling channel, each bit of such a word representing the scan value of a different status/alerting signal at a given moment. The basic tone common to all status/alerting signals may be distributed in coded form on a special or a common channel like voice signals. Any terminal instructed to do so will regenerate any required tone signal for itself.