BPSK vs BOC | Sine BOC modulation | Cosine BOC modulation

This page compares BPSK vs BOC(Binary Offset Carrier) modulation types and describes Sine BOC modulation and Cosine BOC(Binary Offset Carrier) modulation.

GNSS uses channel modulations such as BPSK, BOC (sine and cosine variants), MBOC (Multiplexed BOC) and AltBOC (Alternate BOC).

BPSK Modulation

The equation below denotes BPSK modulated PRN sequence. Here p(t) denotes basic pulse used as binary data stream.

BPSK equation1

No pulse shaping is used in GNSS. Here p(t) = pTc(t) = rectangular pulse

BPSK equations

Here modulated signal is expressed as convolution between code navigation data and modulation pulse. BPSK is the short form of Binary Phase Shift Keying modulation. Refer BPSK modulation➤ which mentions conversion of binary data consisting of 1s and 0s into binary symbols.

Sine BOC Modulation

sine BOC modulation waveforms
Fig.1 Sine BOC modulation Waveforms

BOC modulation is the short form of Binary Offset Carrier modulation. It is called as square subcarrier modulation. Here PRN code which has chip rate of fc is multiplied by rectangular subcarrier having frequency of fsc. This splits the spectrum of the signal.

sine BOC modulation equations

The Sine BOC time waveform is expressed as above.

Cosine BOC Modulation

cosine BOC modulation waveforms
Fig.2 Cosine BOC modulation Waveforms

Cosine BOC can be modelled as double Sine BOC modulation in which first stage has modulation of order NB and second stage has modulation order of 2.

cosine BOC modulation equations

The Cosine BOC time waveform is expressed as above.

PSD Spectrum of BPSK and BOC modulation types

PSD spectrum BPSK BOC modulations
Fig.3 PSD spectrum of BPSK and BOC modulations

The figure depicts PSD spectrum of BPSK modulation, Sine BOC modulation and Cosine BOC modulation.

BPSK QPSK and other Modulation types links

Other than BPSK vs QPSK one can also refer following links which mentions difference between AM vs FM vs PM, ASK vs FSK vs PSK, about modulation basics and modulation types viz. BPSK, QPSK, QAM, 8PSK, DPSK, MSK, GMSK, C4FM vs CQPSK etc.
AM vs FM vs PM  ASK vs FSK vs PSK  what is modulation  MSK and GMSK modulation  8-PSK modulation  QPSK modulation  BPSK modulation  QAM modulation  DPSK Modulation  C4FM vs CQPSK

What is difference between

Refer QPSK vs OQPSK vs pi/4QPSK for difference between QPSK, OQPSK and pi/4QPSK modulation types
difference between OFDM and OFDMA
Difference between SC-FDMA and OFDM
Difference between SISO and MIMO
Difference between TDD and FDD

RF and Wireless Terminologies