Experimental Results on Constant Envelope Signaling with Reduced Spectral Sidelobes

Considerable recent attention has been given to the use of pulse modification to reduce spectral sidelobes in constant envelope data transmission within the "offset" modulation format that includes offset QPSK and MSK. Analytic techniques have been developed which predict probabilistically (without dependence on simulation) the power spectral density that results from pulse modification combined with hard limiting where necessary to achieve constant envelope. Here the computational results are compared with experimental results. Agreement between theory and experiment is seen to be good. The implications for bandwidth efficiency and communication efficiency are discussed.