CDMA direct spread overlay system and method of operation

A CDMA wireless communication system that supports underlay transmissions and direct spread overlay transmissions to a plurality of mobile stations, the CDMA wireless communication system comprising:

• a base station controller;
• a plurality of base stations coupled to the base station controller;
• an underlay base station of the plurality of base stations comprising:
• a base station controller interface that receives underlay communications intended for the plurality of mobile stations;
• an underlay unit coupled to the base station controller interface that receives the underlay communications and produces underlay transmissions, wherein the underlay unit couples the underlay transmissions on a plurality of underlay carriers, and wherein each of the plurality of underlay carriers occupies a respective underlay bandwidth;
• and
• a radio frequency unit that receives the underlay transmissions and transmits the underlay transmissions via an antenna to the plurality of mobile stations;
• an overlay base station of the plurality of base stations comprising:
• a base station controller interface that receives overlay communications intended for the plurality of mobile stations;
• an overlay unit coupled to the base station controller interface that receives the overlay communications and produces overlay transmissions, wherein the overlay unit couples the overlay transmissions on an overlay carrier having an overlay bandwidth that extends across a combined spectrum of the plurality of underlay bandwidths;
• and
• a radio frequency unit that receives the overlay transmissions and transmits the overlay transmissions via an antenna to the plurality of mobile stations;
• and
• the overlay base station producing the overlay transmissions such that they are at least partially orthogonal to the underlay transmissions produced by the underlay base station.

In a CDMA wireless communication system that services a plurality of mobile stations, a method of communicating with the plurality of mobile stations comprising:

• receiving communications intended for the plurality of mobile stations;
• dividing the communications into overlay communications and underlay communications;
• converting the underlay communications into underlay transmissions, wherein the underlay transmissions are coupled on a plurality of underlay carriers, and wherein each of the plurality of underlay carriers occupies a respective underlay bandwidth;
• converting the overlay communications into overlay transmissions that are at least partially orthogonal to the underlay communications, wherein the overlay transmissions are coupled on an overlay carrier having an overlay bandwidth that extends across a combined spectrum of the plurality of underlay bandwidths;
• and
• transmitting the underlay transmissions and the overlay transmissions to the plurality of mobile stations.