Acquisition of packets with a short preamble for direct-sequence spread-spectrum multiple-access packet communications

Abstract

Traditional methods for the acquisition of packets use the a priori information contained in the preamble, which is located at the start of each packet. For spread-spectrum systems such as a direct-sequence spread-spectrum packet communication, the preamble consists of a short period of known code sequence and the code sequence continues until the end of the packet, i.e., the information that may be useful for the acquisition continues even after the preamble period for spreading of message symbols. In this work, for direct-sequence packet communications we. propose a technique to enhance the performance of a packet acquisition system which uses not only the preamble but also the message payloads that follow the preamble. The proposed method is a tradeoff between the accuracy in the declaration of acquisition and receiver complexity. Using the proposed method we improve the probability of acquiring packets that leads to an increase in the throughput of the packet system, which is defined as the average number of successful packets given the offered traffic.