Improving Automatic Position Reporting System (APRS) throughput and reliability
Thesis (MScEng (Electrical and Electronic Engineering))--University of Stellenbosch, 2005.
The Automatic Position Reporting System (APRS) is a well-established packet communication protocol that offers users a graphical position display system and a peer-to-peer textual message service. APRS is used in temporary and mobile networks where rapid deployment of infrastructure is required and limited a priori knowledge of the network topology is available. The APRS protocol can be used for emergencies and public service applications. ARPS, functioning as an access network, was originally designed to require low complexity and support high flexibility of a network. These design directives have limited APRS’s performance by resulting in low throughput and poor reliability. In order for APRS to be used in time-critical applications, these limitations would need to be improved. The thesis considers the limitations of ARPS by proposing an improved protocol stack with a substitution of the media access control (MAC) layer. The new protocol is modelled in order to develop a largely platform-independent implementation, which could be efficiently retargeted for different platforms. Lastly, a protocol performance evaluation is done in order to determine the resulting improvements on APRS and the overall viability of the proposal.