Bandwidth Enhancement Techniques for Large-Area VLC Receivers

The work reports, for the first time, the use of Linvill’s negative impedance converter (NIC) to generate negative resistance and inductance for the purpose of extending the bandwidth of optical receivers used in visible light communication (VLC). The work shows that the bandwidth-limiting series resistance, inherent in large-area photodiodes, can be compensated by using a simple NIC circuitry generating a compensating negative resistance in series with a negative inductive reactance. Mathematical derivations and simulations are verified by experimental results showing a bandwidth extension of up to 400% when used with only minimal additional circuit elements.