Adaptive synchronization and integration region optimization for energy detection IR-UWB receivers

Non-coherent energy detection (ED) IR-UWB receivers exhibit strong advantages in low data rate, low power and low cost applications such as RFID and Wireless Sensor Networks. However, the performance of ED receivers is usually suffered from the noise enhancement due to the large time-bandwidth product. The integration region of the receiver integrator significantly affects the bit error rate (BER) performance. This paper presents a method of synchronization and estimating the optimal integration region (i.e., the starting point and the length of the integration window), which is based on the analysis of received signal energy capture and combined with a time of arrival (TOA) estimation. The proposed scheme is based on the symbol rate sampling and does not require a priori information about the channel delay profile. Besides, it can adapt to various indoor channel environments. The algorithm has a moderate accuracy but a very low complexity and fast synchronization speed. The validity of the proposed approach is demonstrated by numerical results using IEEE 802.15.4a channel models.