(a) A high impedance integrating front end preamplifier is used in an optical fibre receiver operating at a wavelength of 1.55µm in parallel with a detector bias resistor of 200kO. The effective input resistance of the preamplifier is 0.5MO and the total capacitance is 3pF. Calculate the bandwidth and thermal noise (per unit bandwidth) of this receiver. State any assumptions made.
(b) Assuming Gaussian statistics for the noise, evaluate the sensitivity the receiver in Q1(b) at an error rate of 10-9 . State any assumptions made.
Sample Solution