A Survey of Advanced Neuro Fuzzy Based AGC Circuit for High-Frequency Signals

Automatic gain control (AGC) is an essential block in many applications like wireless transreceiver, disk drive read channels, etc. it is a closed-loop feedback regulating circuit in an amplifier to maintain amplitude at its output despite variation of the signal amplitude at the input. Any mismatch between generation and requirement causes the system frequency and terminal voltage to deviate from the required value. In this paper, dynamic and uncertain performance of reactive AVR (Automatic voltage Regulator) and active Load frequency control (LFC) of AGC Is achieved by NFLC (Neuro Fuzzy Logic Circuit). Fuzzy logic depends on the existence of a expert to determine The inference logical rules and NN is controlled by several input and output patterns. Neural Network have high learning capacity the fuzzy rules and interoperate form them. So the Disadvantage of fuzzy can be Compensated by NFLC. NFLC is placed in the feedback path to tune AGC for error compensation like noise, amplitude variation, stable voltage, etc. Apart from this power supply fluctuations are suppressed with this controller. Hybrid approach for Neuro fuzzy based AGC provides fast and reduced computational time for high Frequency signal (in terms of GHz) is proposed. Thus, a higher gain for higher frequency signal can be achieved.