For example, a quadrature phase-shift keying
(QPSK) signal can be examined to determine how different values of a affect the vector diagram.
The digital communication formats include spread spectrum, quadrature amplitude modulation, AM and quadrature phase-shift keying
d Ka-band linearizer decreases the spectral regrowth of single-carrier quadrature phase-shift keying
and digitally modulated signals.
A second data modulation format, offset quadrature phase-shift keying
(OQPSK), is favored due to its ease of implementation and relatively constant carrier envelope.
The tracking range is [+ or -]2 MHz for 64 kbps binary phase-shift keying (BPSK) or 128 kbps for quadrature phase-shift keying
(QPSK), and [+ or -]1 MHz for 1 Mbps BPSK or 2 Mbps QPSK.
IS-136, which uses [Pi]/4 differential quadrature phase-shift keying
(DQPSK) modulation, is a next-generation version of the IS-54B standard already in use in the cellular band.
This technology applies to a variety of products including biphase- and quadrature phase-shift keying
modulators, vector modulators, phase shifters and phase-free attenuators.
Ordinary power meters are designed and calibrated for sine waves, and binary phase-shift keying (BPSK) and quadrature phase-shift keying
(QPSK) modulated signals, and cannot perform accurate noise power measurements.
Numerous digital modulation techniques are in use around the world today; prevalent and proven among these techniques are quadrature amplitude modulation (QAM) and quadrature phase-shift keying