1. QPSK Receiver

2. QPSK Receiver
Integrate
&
Dump MF
2 stufiger Prozess

3. Phasor diagram
We can represent the BPSK signal using a phasor diagram which shows the two possible BPSK states.
This is referred to as a signal constellation.
90˚
180˚ = binary 0
0˚ = binary 1
180˚ 0˚
270˚

4. Noise effects - BPSK 0˚ 180˚ 90˚ 270˚ 20 dB SNR 10 dB SNR 90˚ 0˚ 180˚

5. QPSK Receiver

6. M-ary PSK
In order to increase the data rate without increasing bandwidth, we can further increase the number of bits per symbol.
In the 8-PSK constellation below, 8 possible phase shifts allow 3 bits to be transmitted by each symbol.
0˚ = binary 000
45˚ = binary 001
90˚ = binary 011
315˚ = binary 100
270˚ = binary 101
135˚ = binary 010
180˚ = binary 110
225˚ = binary 111 0˚
180˚
90˚
270˚

7. Noise effects (8-PSK) What is the relative likelihood of an error? 0˚
180˚
90˚
270˚
10 dB SNR
What is the relative likelihood of an error?

8. Squaring loop Recover frequency using squaring Lowpass Filter Squaring
Device
Bandpass
Limiter
(or PLL)
Frequency
Divider

9. Costas Loop 180 Grad Unsicherheit engl. „Phase Ambiguity“
Bekannte Präambel notwendig

10. Costas loop Goal of Costas loop: e0 Baseband LPF VCO -90
Phase shift