This signal is then given to the integrator and bit synchronizer unit. This carrier is then multiplied with the input signal, As it is frequency divider by 2 thus generates a carrier with frequency f c. This signal is then further fed to a frequency divider unit. This BPF has a centre frequency of 2f c, eliminates the dc level hence, generates output as This signal is then fed to the BPF as we can see in the diagram above. Here, only the carrier of the signal is taken into consideration thus the amplitude is neglected.Įxpanding the carrier as the above mathematical identity, The signal is then fed to a square law device that provides The phase shift ɸ is based on the time delay in between transmitter and receiver. Let us consider, the signal at the input of the receiver is The block diagram for the coherent detection of BPSK signal is shown below: When the bit sequence changes from 0 to 1 then we noticed a positive phase change whereas, when the bit sequence changes from 1 to 0 then a negative change of phase is noticed. Here, as we can see that, the figure shows phase reversal when the bit sequence gets changed either from 1 to 0 or from 0 to 1. The resultant BPSK signal is then achieved. Here, (i) represents the binary bit sequence, the next represents the bipolar NRZ sequence m(t) that is used to modulate the carrier wave represented in (iii). Let us have a look at the figure below that shows BPSK generated waveform with the binary bit sequence and carrier wave. Thus, the binary signal modulates the carrier wave that generates a phase shifted modulated signal termed as BPSK signal. This bipolar NRZ signal is fed to the balanced modulator along with the carrier wave. The binary message signal is fed to the bipolar NRZ level encoder that converts the Binary data input into equivalent bipolar NRZ sequence m(t).
The figure below shows the block diagram for the generation of a BPSK signal.Īs we can see here that the system consists of NRZ encoder along with product modulator and carrier generator. : b(t) will be +1 in case of transmission of binary 1 andī(t) will be -1 in case of transmission of binary 0.