We propose a novel wireless technique named pinpoint waveforming to achieve the location-restricted service access control, i.e., providing wireless services to users at eligible locations only. The proposed system is inspired by the fact that when two identical wireless signals arrive at a receiver simultaneously, they will constructively interfere with each other to form a boosted signal whose amplitude is twice of that of an individual signal. As such, the location-restricted service access control can be achieved through transmitting at a weak power, so that receivers at undesired locations (where the constructive interference vanishes), will experience a low signal-to-noise ratio (SNR), and hence a high bit error rate that retards the correct decoding of the received messages. At the desired location (where the constructive interference happens), the receiver obtains a boosted SNR that enables the correct message decoding. To solve the difficulty of determining an appropriate tra...