Ir-uwb Rf Transceiver Research And Design

UWB (Ultra Wideband) is one of the wireless personal area network technologies; its main applications include imaging systems, vehicular radar systems and communications and measurement systems. Ever since the FCC released an unlicensed spectrum of 3.1-10.6 GHz for UWB application in 2002, UWB has received significant interests both in industries and academics world. Because of its ultra wideband channel, the transmission data rate of UWB can be as high as 500 Mb/s, which is much faster than other short range communication systems. On the other hand, the emitted spectrum density of UWB must be less than -41.3 dBm/MHz, which make UWB easy to coexist with other existing communication systems. Because of its pending standard, there are many UWB system architectures. In this dissertation, a 3-5 GHz carrier-less pulse UWB (IR-UWB) is proposed with maximum data rate of 100 Mb/s.IR-UWB transmitter directly generates RF pulses by differentiating Gaussian pulses and it needs no DAC, mixer and PLL. IR-UWB transmitter has the advantage of low complexity and low power; however, it has difficulty in controlling its output spectrum because of the process deviations. In this dissertation, a BPSK and OOK modulated output pulse amplitude and spectrum tunable pulse generator is proposed to solve this problem. The output buffer of the transmitter can be turned off between the pulses intervals to save power.The noncoherent architecture is employed in the receiver design. Noncherent receiver needs no PLL and template pulse generator and it has low precision requirement on the synchronization; however, its noise performance is worse than the coherent receiver. In the receiver, the received pulses are firstly amplified by the low noise amplifier and then down-converted to analog baseband by the correlator. The low noise amplifier adopts the architecture of single input differential output with an on-chip balun; the correlator employs the characteristic of the IR-UWB system discrete pulses to omit the sample-and-hold circuit; programmable gain amplifier and low pass filter choose open loop and Gm-C topologies respectively to realize wideband applications and the synchronization block employs an open loop delay line according to the low requirement on the precision.In this dissertation, three chips-IR-UWB transmitter, receiver and monolithic transceiver are verified in 0.13μm CMOS technology. The chip area of the transceiver is 2 mm X 2 mm, and the power consumption of the transmitter and receiver is 2.2 mW and 13.2 mW, respectively. The 3 step peak-to-peak amplitudes of the output pulse of the transmitter are 240 mV,170 mV and 115 mV and the tunable range of center frequency is 3.2-4.1 GHz. The receiver shows a maximum gain of 70 dB and the noise figure and the input 1 dB compression point is 8.6 dB and-28 dBm, respectively. BER measurement of the wireless transceiver system using off-chip antennas is also shown, and the receiver achieves a sensitivity of-50 dBm with a BER of 1‰.