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M. El Ghzaoui and S. Das
0
1
2
3
4
5
6
7
8
9
10
10
-2
10
-1
10
0
EbNo(dB)
BER
Roll Off=0.1
Roll Off=0.2
Roll Off=0.25
Fig. 8 BER of QPSK modulation under proposed channel model
300 GHz MMW signal
BPF
Downconversion
IF/LPF
ADC
BPF
Downconversion
LNA
IF/LPF
ADC
Carrier
recovery
And IQ
separation
Detecon
Data
In
QPSK/BPSK
BPF
Upconversion
PA
DAC
Differena
l Encoding
QPSK/BPSK
BPF
Upconversion
PA
DAC
S
p
li
tt
e
r
Fig. 9 Block diagram of MIMO-QPSK/BPSK transceiver system
Pseudorandom bit sequence generator having a block length of 229-1 is passed
on the 300-GHz symbol modeled by QPSK/BPSK schemes. The central frequency
of the received IF signal was 55.5 GHz and the bandwidth is about 60 GHz. At phase
demodulator, the digital signal which modulates the amplitude of carrier, as well as
the phase of the carrier, was multiplied with a complex sinusoidal signal to separate
the I and Q components. To reduce the signal processing complexity, our studies are
mainly founded on a BPSK/QPSK system with receiving techniques like frequency