Spectrum sharing feasibility for CDMA PCS

To investigate the application of spread spectrum Code Division Multiple Access (CDMA) technology. To the future personal communications services (PCS), a comprehensive study of CDMA PCS in the 1.8 GHz band in various radio environments has been conducted by Telesis Technologies Laboratory (TTL) in cooperation with Qualcomm Inc. in San Diego. We present the results of TTL´s study on spectrum sharing feasibility for CDMA PCS. The study demonstrated that in rural and suburban areas, where microwave beams are generally well confined and easy to be predicted, it is possible to significantly reduce the PCS forward link interference to OFS by carefully facilitating coordination between microwave terminals and PCS base stations. The CDMA spectrum sharing capabilities can be substantially improved by taking advantage of rigorous power control for the CDMA systems. In the case of the mobile stations inside the microwave beam, the unique feature of soft hand-off for CDMA systems shows significance in reducing interference to the fixed microwave