Digital modulation performance assessment for the GTE Airfone GenStar system

The second generation GTE Airfone Public Correspondence System, GenStar, will employ digital transmission to improve performance, increase service offerings and provide for future capacity enhancements. With 6 kHz channel spacing and an aggressive throughput target, high-level modulation schemes were considered early in the system design. By analysis and measurement, 16 QAM was determined to be a suitable candidate for this application. The authors describe the assessment of 16 QAM as a transmission technique for the commercial air-to-ground transmission channel.<
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