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HOME  >  ANSL R&D Times  >  No.38_1 (2004_04)  >  15.Adaptive modulation function
ANSL R&D Times

15.Adaptive modulation function

An AP can automatically change the modulation scheme depending on the quality of the wireless circuit by using an adaptive modulation function for each WT. For example, if the circuit quality for a WT that uses 16 QAM becomes poor, the AP changes the modulation scheme for the WT to QPSK. If the circuit quality improves, it changes the modulation scheme to 16QAM. Each WT measures its own circuit quality and reports the measurement results to the AP for the adaptive modulation function.

 

Fig. 14 Effectiveness of adaptive modulation

Fig. 14 Effectiveness of adaptive modulation