Slot Synchronization in Ad Hoc Networks Based on Frequency Hopping Synchronization

Abstract

To realize Time Division Multiple Access (TDMA) in ad hoc networks, a new slot synchronization scheme based on frequency hopping (FH) synchronization was proposed. In this scheme, every node in the network uses a slot counter to position slots. By compensating the time when the separator is detected with the estimated delays, the receiver's slot counter can synchronize to the sender's. Guard intervals are used in nodes to avoid collisions caused by the synchronization error. As the proposed scheme can avoid transmitting concrete time information in the network, the channel utilization can be improved. Simulation results show that the channel utilization of the proposed scheme is higher than other schemes. Moreover, this scheme has a small synchronization error and only needs a short time period to realize the initial slot synchronization. Therefore, it can be applied to real ad hoc networks.

Performance Analysis of Frequency Hopping Ad Hoc Communication System With Non-Orthogonal Multiple Access

“…Based on the results of ( 9), ( 15), (17) and Lemma 3, after some further mathematical manipulations, we can express the coverage probability of a typical receiver according to the following theorem:…”

Slot Time Synchronization for TDMA-Based Ad Hoc Networks

“…Where, T offset = T send -T arrive Time synchronization of two nodes can be acquired from receiving the message that contains the sender' time stamp using equation (3). Many protocols ,such as TPSN [10]、FTSP [11], get the time stamp from given bytes in the sending message.…”

“…To achieve this we can use two methods. The first is by receiving time from a Global Position System (GPS) [2], which can provide a high precision; however this information is not available in some situations especially in the battlefield [3]. In addition, GPS receivers are expensive.…”