QPSK Phase Shift: Symbol Change Explained

AI Thread Summary
QPSK, or Quadrature Phase Shift Keying, utilizes coherent modulation where the receiver's reference clock is synchronized with the incoming signal. When a symbol change occurs in QPSK, the phase of the signal is altered to represent different data points, effectively encoding information through these phase shifts. The discussion highlights the importance of understanding how these phase shifts relate to the modulation process. Visual aids, such as diagrams, can help illustrate these concepts more clearly. Understanding QPSK phase shifts is crucial for effective communication in digital signal processing.
bhanesh
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What is phase shift of qpsk when symbol change occurs ?

Can anybody explain please ?
 
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QPSK is a form of "coherent" modulation. In coherent modulation the receiver contains a reference clock that is frequency locked to the received signal. Data is encoded by changing the received signal's phase and amplitude relative to the reference clock. Phase shifts are illustrated in the attached picture.
 

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bhanesh said:
What is phase shift of qpsk when symbol change occurs ?

Can anybody explain please ?

Did you look at Wikipedia? Have you any questions about their treatment of QPSK?
 

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