## Offset QPSK (OQPSK)

#### Offset QPSK can be used in place of p/4 QPSK to achieve the same end, that is, a non-zero envelope in the modulated signal. Offset QPSK is implemented by staggering the input data streams to the two quadrature BPSK modulators by half a symbol period. The remainder of the modulator and demodulator circuits remains identical to that for conventional QPSK. (The staggered timing must be removed in the receiver.) |

| #### For both p/4 QPSK and Offset QPSK, the BER performance, assuming ideal coherent detection, is identical to that of QPSK itself.