Method to facilitate late joining of a call

Abstract

Methods of enabling late entry into an on-going spread spectrum call are described. A late join frame replaces, and has the same size as, a traffic frame. A late join slot in the late join frame contains sufficient information in preamble and sync subframes to permit a target to join the call. The traffic slots in the late join frame replicate data such that call quality of the call is substantially unaffected if one of the remaining traffic frames is not received. The preamble and sync subframes frequencies may be the same as, or different from, preamble and sync frames frequencies during a call establishment phase of the call. If different, the preamble and sync subframes frequencies are selected from one or more frequencies. Use of the preamble and sync subframes frequencies is compensated for when selecting the traffic slot frequencies to obtain uniform utilization of the spectrum.