The term "diversity" in radio systems refers to the use of multiple signal paths, such as in multipath conditions, as an advantage. The goal is to maximize the likelihood that a transmitted data packet will be correctly received. According to an application note titled "Implementing Diversity' Using Low Power Radios" by Mike Burns and Tim Starr, such techniques can be implemented using one or two low-power radios, a low-power microcontroller, and an external RF switch.
The 16-page document details techniques for implementing the following: single-radio amplitude-based antenna diversity (two antennas and one radio), dual-radio antenna diversity (two antennaseach connected to a radio), and single-radio frequency diversity (one antenna, one radio, and two frequencies). The effectiveness of the three approaches was tested in experiments that placed the transmitter in a main hallway in an office building.
The receiver was placed about 150 ft. away behind a series of walls and doors. It was mounted to the moving platform of a 60-in. linear actuator, which was set to move 60 in. in the time it takes to transmit 1000 data packets. The note ends with a table showing the pros and cons of each approach. All of the techniques effectively minimized multipath effects.
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