Howtosignalprocessing
- How many phases are transmitted in DPSK?
- Why do we use phase shift keying?
- Why do we need 1 bit delay in DPSK modulator and demodulator?
- How synchronization problem is avoided for dpsk detection?
How many phases are transmitted in DPSK?
DPSK encodes two distinct signals, i.e., the carrier and the modulating signal with 180° phase shift each.
Why do we use phase shift keying?
It is widely used for wireless LANs, RFID and Bluetooth communication. Any digital modulation scheme uses a finite number of distinct signals to represent digital data. PSK uses a finite number of phases, each assigned a unique pattern of binary digits. Usually, each phase encodes an equal number of bits.
Why do we need 1 bit delay in DPSK modulator and demodulator?
In DPSK demodulation, DPSK signal is passed to the balanced modulator and 1 bit delay circuit. The resulting signal is passed to the LPF which produces binary data. This is passed to comparator circuit (or Schmitt trigger circuit) to produce clean and high speed binary levels.
How synchronization problem is avoided for dpsk detection?
DPSK does not need a synchronous (coherent) carrier at the demodulator. The input sequence of binary bits are modified such that the next bit depends upon the previous bit. Therefore, in the receiver, the previous received bits are used to detect the present bit.
