An Energy-Efficient IR-UWB Receiver Based on Distributed Pulse Correlator

A new circuit technique called distributed pulse correlator (DPC) is proposed for pulse detection in ultra-wideband impulse radio (IR-UWB) receivers. Among several IR-UWB transceiver architectures, an analog correlation receiver has the advantages of good performance and reduced circuit complexity, but requires a correlator and a template pulse with good time resolution. To achieve both fine time resolution and low power consumption, a DPC time-interleaves multiple sampling stages operating in a power-saving pulsed mode and incorporates a built-in mechanism to generate the reconfigurable local template pulse. The operation of the DPC is theoretically analyzed and its performance evaluated, followed by a detailed discussion of its circuit implementation. A chip prototype of a 3-10-GHz analog correlation receiver employing an eight-tap, 10-GSample/s DPC was designed and fabricated in a 0.18-μm standard digital CMOS technology. In the measurement, the DPC achieves a pulse rate of 250 MHz with an energy efficiency of 40 pJ/pulse, and the whole receiver achieves an energy efficiency of 190 pJ/pulse at the 250-MHz pulse rate. The complete IR-UWB link (a transmitter, a receiver, and antennas) is also tested.