Patent ID: 9234955
Filing Date: 2016-01-12
CPC Classification: G01S,H01Q,H04B

Claim Text:
1. A rod antenna circuit comprising: a first antenna coil wound on a former, the first antenna coil providing first and second output connections at opposite ends of the first antenna coil, and the first antenna coil comprising a centre tap that is AC grounded via a capacitive coupling between the centre tap and an electrical ground; a differential amplifier having inverting and non-inverting inputs, the inverting input receiving a first signal derived from one of the first and second output connections, and the non-inverting input receiving a second signal derived from the other of the first and second output connections, the differential amplifier providing a differential output signal dependent upon the first and second signals; and a feedback coil magnetically coupled to the first antenna coil and arranged to be fed a feedback signal derived from the differential output signal so as to provide negative feedback to the first antenna coil.