A balanced amplifier circuit is shown below. The two amplifiers are identical, each with power gain G and noise figure F. The two quadrature hybrids are also identical, with an insertion loss from the input to either output of L > 1 (not including the 3 dB power division factor). Derive an expression for the overall noise figure of the balanced amplifier. What does this result reduce to when the hybrids are lossless?
