1.1 Binary phase shift keying (BPSK)

Binary phase shift keying (BPSK) is simplest form of phase shift keying (PSK).It uses two phases which are separated by 180⁰ .And it is also termed as 2-PSK,the Bit Error Rate (BER)of BPSK in AWGN can be calculated as

The constellation diagram of BPSK signal is as follows.

Fig 1.1: Constellation diagram of BPSK

In this bits are converted into antipodal noise symbols. It is unsuitable for high data rate applications because it is only modulate 1bit/symbol. BPSK is functionally equivalent to 2-QAM modulation.