# 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.

No pulse shaping is used in GNSS. Here p(t) = p_{Tc}(t) = rectangular pulse

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

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 f_{sc}.
This splits the spectrum of the signal.

The Sine BOC time waveform is expressed as above.

## Cosine BOC Modulation

Fig.2 Cosine BOC modulation Waveforms

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

The Cosine BOC time waveform is expressed as above.

## PSD Spectrum of BPSK and BOC modulation types

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

C4FM vs CQPSK

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

FDMA vs TDMA vs CDMA

FDM vs TDM

CDMA vs GSM