Abstract: The invention discloses a golf ball tracking system, which includes a distributed sensor and processor system adapted to simultaneously track the trajectories of multiple golf balls hit by one of more golfers. The system is adapted to keep track of the location of the golfers to enable the allocation of shots to the correct golfer. The system is operated at a golf driving range, where multiple players can hit balls from anywhere within a designated area and/or fixed hitting bay locations. Multilateration is used to determine the location of multiple targets in 3D space, based on the reported range and Doppler from distributed radar sensors.

Abstract: An embodiment provides a continuous-time delta-sigma modulator for analog-to-digital conversion. The modulator includes a signal path generating including a ring voltage controlled oscillator driven by an analog input signal. The signal path produces digital values by sampling the ring voltage controlled oscillator. A calibration circuit measures nonlinear distortion coefficients in a replica of the signal path. A nonlinearity corrector corrects the digital values based upon determined nonlinear distortion coefficients. Preferred embodiment ADC ?? modulators do not require any analog integrators, feedback DACs, comparators, or reference voltages, and do not require a low jitter clock.