Ethernet via Bidirectional Packet Based Telemetry – Frequency Division Duplex (FDD) vs. Time Division Duplex (TDD)

Abstract

An analysis of the implementation and application of two approaches to bidirectional packet-based telemetry: Frequency Division Duplex (FDD) and Time Division Duplex (TDD). The dual channel FDD system approach has two parallel links providing low latency with co-site interference considerations. The TDD Switched Telemetry System (SwTS) approach requires only one frequency which completely eliminates the co-site interference issue though introduces packet latency, transmitter switching and receiver synchronization considerations. This paper includes analysis of these two approaches including measured networked telemetry data from lab testing. How each of these two systems are configured based on a set of application specific requirements will be covered as well as the performance results when they are subjected to the same RF impairment and user traffic conditions.