Quadrature phase-shift keying (quadriphase, quaternary phase-shift keying) is a form of modulation in which a carrier is sent in four phases, 45, 135, 225, and 315 degrees, and the change in phase from one symbol to the next encodes two bits per symbol. In QPSK, the four angles are usually out of phase by 90°.This a significant advantage over the normal Phase shift Keying of two values effectively doubling the bandwidth.
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Example Usage of QPSK
dsplog: [comment on dspLog] Dear krishna, lots of engineers are ask for the MIMO 2x1 with QPSK. And I changed your source, ... http://bit.ly/5YTnwm
John_Mockler: RT @CMLMicro: RF Applications for: FFSK/MSK/FSK/GMSK/QPSK/QAM / Wireless telemetry / Marine AIS systems plus many more! visit www.cmlmic ...
CMLMicro: RF Applications for: FFSK/MSK/FSK/GMSK/QPSK/QAM / Wireless telemetry / Marine AIS systems plus many more! visit www.cmlmicro.com 4 more info
