Journal of Communications
Line-of-sight optical wireless channels are emerging as a promising broadband wireless access technology. This paper describes a front-end Trans-Impedance Amplifier (TIA) that is designed to overcome challenges faced by high-speed optical wireless links requiring receivers with wide Field-Of-View (FOV) and high dynamic range for signal acquisition/tracking. This trans-impedance amplifier employs a capacitive feedback configuration, with a self-biased Automatic Gain Control (AGC) circuit to increase the input dynamic range. The trans-impedance amplifier is designed for integration with wide FOV detectors with associated capacitance up to 5pF and its performance is insensitive (within 5%) to an order of magnitude variation in input capacitance.