Difference Between Amplifier and Receiver

放大器和接收器

Amplifier and receiver are two types of necessary circuits used in communication. Usually a communication happens between two points called transmitter and receiver through a wired or wireless medium. Transmitter sends a signal containing some information and receiver grabs that signal in order to reproduce that information. After travelling some distance, usually, a signal get weakened (attenuated) due to energy loss in the medium. Therefore, once this weak signal is received at the receiver, it should be improved (or amplified). Amplifier is the circuit which magnifies the weak signal to a signal with more power.

Amplifier

Amplifier (also shortened as amp) is an electronic circuit, which increases the power of an input signal. There are many types of amplifiers ranging from voice amplifiers to optical amplifiers at different frequencies. A transistor can be configured as a simple amplifier. The ratio between output signal power to input signal power called as the ‘gain’ of the amplifier. Gain may be any value depending on the application. Usually gain is converted into decibels (a logarithmic scale) for convenience.

Bandwidth is another important parameter for amplifiers. It is the frequency range of the signal which amplified in expected way. 3dB bandwidth is a standard measure for amplifiers. Efficiency, linearity and slew rate are some of other parameters to be considered when designing an amplifier circuit.

Receiver

Receiver is the electronic circuit which receives and regenerates a transmitted signal from a transmitter through any medium. If the medium is wireless radio, receiver may consist of an antenna to convert the electromagnetic wave into an electrical signal and filters to remove unwanted noise. Sometimes receiver unit may also include amplifiers to amplify the weak signal and decoding and demodulation unit to reproduce the original information. If the medium is wired, there won’t be an antenna and it may be replaced by a photo detector in optical signaling.

Difference between amplifier and receiver 1. In many cases, amplifier is a part of the receiver. 2. Amplifier is used to magnify a signal, whereas receiver is used to reproduce a signal sent at a transmitter 3. In many cases amplifier may be a part of a receiver 4. Sometimes, amplifiers introduce some noise to the signal where receivers are always made to eliminate noise.