The most fundamental digital modulation techniques are based on keying: PSK (phase-shift keying): a finite number of phases are used. FSK (frequency-shift keying): a finite number of frequencies are used. ASK (amplitude-shift keying): a finite number of amplitudes are used.
Read moreWhy are digital modulation techniques used in satellite communication?
The advantages provided by digital modulation techniques include: Better performance . Better Error detection and correction efficiency. Better Signal to noise ratio so less prone to interference or noise.
Read moreWhat are modulation techniques?
Modulation is the process of converting data into electrical signals optimized for transmission. Modulation techniques are roughly divided into four types: Analog modulation, Digital modulation, Pulse modulation , and Spread spectrum method .
Read moreWhat is a satellite modulator?
A satellite modem or satmodem is a modem used to establish data transfers using a communications satellite as a relay . A satellite modem’s main function is to transform an input bitstream to a radio signal and vice versa.
Read moreWhat is difference between BPSK and QPSK?
As mentioned above in the table, BPSK represents binary input 1 and 0 w.r.t. change in carrier phase by 180 degree. While QPSK represents two bits using complex carrier symbol each having 90 degree shift with one another .
Read moreWhy BPSK is used?
BPSK Applications It is used in OFDM and OFDMA to modulate the pilot subcarriers used for channel estimation and equalization . As we know different channels are used for specific data transmission in cellular systems.
Read moreWhat is the principle of BPSK?
BPSK can be considered as a form of amplitude shift keying where each nonreturn to zero (NRZ) data bit of value 0 is mapped into a −1, and each NRZ 1 is mapped into a + 1. The resulting signal is then passed through a filter to limit its bandwidth and then multiplied by the carrier signal cos ωt (see Figure 4.2).
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