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A more practical scheme is differential binary phase-shift keying, in which the carrier remains at the same frequency, but can be in one of two phases. During each symbol, the phase either remains the same, encoding a 0, or jumps by 180°, encoding a 1. Again, only one bit of data (i.e., a 0 or 1) is transmitted by each symbol. This is an ...
Multiple frequency-shift keying (MFSK) is a variation of frequency-shift keying (FSK) that uses more than two frequencies. MFSK is a form of M-ary orthogonal modulation , where each symbol consists of one element from an alphabet of orthogonal waveforms.
An OFDM carrier signal is the sum of a number of orthogonal subcarriers, with baseband data on each subcarrier being independently modulated commonly using some type of quadrature amplitude modulation (QAM) or phase-shift keying (PSK). This composite baseband signal is typically used to modulate a main RF carrier.
The IEEE 1902.1-2009 standard [1] is a wireless data communication protocol also known as RuBee, operates within the Low Frequency radio wave range of 30–900 kHz. Although very resistant to interference, metal, water and obstacles, it is very limited in range, usually only suitable for short-range networks.
The C/A code is transmitted on the L1 frequency as a 1.023 MHz signal using a bi-phase shift keying modulation technique. The P(Y)-code is transmitted on both the L1 and L2 frequencies as a 10.23 MHz signal using the same BPSK modulation, however the P(Y)-code carrier is in quadrature with the C/A carrier (meaning it is 90° out of phase ).
A phase shift module is a microwave network module which provides a controllable phase shift of the RF signal. [ 1 ] [ 2 ] [ 3 ] Phase shifters are used in phased arrays . [ 4 ] [ 5 ] [ 6 ]
EDR uses a combination of GFSK and phase-shift keying modulation (PSK) with two variants, π/4-DQPSK and 8-DPSK. [81] EDR can provide a lower power consumption through a reduced duty cycle. The specification is published as Bluetooth v2.0 + EDR, which implies that EDR is an optional feature. Aside from EDR, the v2.0 specification contains other ...
For very high bandwidth efficiency, coherent modulation can be used to vary the phase of the light in addition to the amplitude, enabling the use of QPSK, QAM, and OFDM. "Dual-polarization quadrature phase shift keying is a modulation format that effectively sends four times as much information as traditional optical transmissions of the same ...