dpsk การใช้

• Delay line interferometers are also known as optical DPSK demodulators.
• The DPSK decoding method is achieved by comparing the interfere each other constructively or destructively.
• When differential encoding is used in this manner, the scheme is known as differential phase-shift keying ( DPSK ).
• A typical optical system for such a purpose is Mach-Zehnder interferometer or Michelson interferometer, forming an optical DPSK Demodulator.
• Since this scheme depends on the difference between successive phases, it is termed differential phase-shift keying ( DPSK ).
• Differential phase shift keying ( DPSK ) is a common form of phase modulation that conveys data by changing the phase of the carrier wave.
• The waveforms for DPSK are the same as for differentially encoded PSK given above since the only change between the two schemes is at the receiver.
• A demodulator for optical DQPSK signals can be constructed using two matched DPSK demodulators with phase off-set at \ pm \ pi / 4.
• Since this scheme depends on the difference between successive phases, it is termed "'differential phase-shift keying ( DPSK ) " '.
• The term Enhanced Data Rate ( EDR ) is used to describe ? / 4-DPSK and 8DPSK schemes, each giving 2 and 3 Mbit / s respectively.
• Finally, the IEEE 802.15.4a PHY standard actually mixes CSS encoding techniques with differential phase shift keying modulation ( DPSK ) to achieve better data rates.
• If differential modulation such as DPSK or DQPSK is applied to each sub-carrier, equalization can be completely omitted, since these non-coherent schemes are insensitive to slowly changing amplitude and phase distortion.
• Bluetooth 2 will use \ pi / 4-DQPSK at its lower rate ( 2 Mbit / s ) and 8-DPSK at its higher rate ( 3 Mbit / s ) when the link between the two devices is sufficiently robust.
• DPSK can be significantly simpler to implement than ordinary PSK since there is no need for the demodulator to have a copy of the reference signal to determine the exact phase of the received signal ( it is a non-coherent scheme ).
• DPSK can be significantly simpler to implement than ordinary PSK, since there is no need for the demodulator to have a copy of the reference signal to determine the exact phase of the received signal ( it is a non-coherent scheme ).
• In this application, an incoming differential phase-shift keying ( DPSK ) optical signal is first split into two equal-intensity beams in two arms of a Mach Zehnder or Michelson interferometer, in which one beam is delayed by an optical path difference corresponding to " 1-bit " time delay.
• Working principle of optical DPSK demodulation : ( a ) Incoming DPSK signal with uniform intensity, ( b ) 1-bit delay of the incoming DPSK signal with uniform intensity, and ( c ) Demodulated intensity signal after interference between ( a ) / ( a') and ( b ) / ( b').
• Working principle of optical DPSK demodulation : ( a ) Incoming DPSK signal with uniform intensity, ( b ) 1-bit delay of the incoming DPSK signal with uniform intensity, and ( c ) Demodulated intensity signal after interference between ( a ) / ( a') and ( b ) / ( b').
• Working principle of optical DPSK demodulation : ( a ) Incoming DPSK signal with uniform intensity, ( b ) 1-bit delay of the incoming DPSK signal with uniform intensity, and ( c ) Demodulated intensity signal after interference between ( a ) / ( a') and ( b ) / ( b').
• CSRZ-OOK, in which data is coded on the intensity of the signal using a binary scheme ( light on = 1, light off = 0 ), or CSRZ-DPSK, in which data is coded on the differential phase of the signal, etc . CSRZ is often used to designate APRZ-OOK.