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The warrior to warrior communication system is a key element for digitizing the battlespace. Power efficiency, wideband operation for security, and specified bit error rate and availability are the principal requirements. The RF carrier frequencies being considered for this application range from 2 MHz to 2 GHz. This paper presents the results of a study, whose objective was to evaluate the RF link over the frequency range of interest, as an aid in the selection of a carrier frequency for achieving the largest possible coverage for the warrior to warrior communication system. The main components of the RF link are the power radiated by the transmit antenna,the propagation loss, and the background noise level at the receive antenna. Unique to this study is the quantification of the power radiated by the transmit antenna that is consistent with the safety standard for human exposure to RF electromagnetic fields. Over the frequency range of interest the radiated power is limited by the safety standard, in addition, at the lower frequencies, the available antenna volume limits the power that is raided. The propagation los consists of four factors, (1) free space and ground factor, (2) slow fade factor, (3) fast fade factor and (4) building penetration factor. Each of these factors is evaluated separately over the entire frequency range. The background noise at the receive antenna port is found in the literature. The measure of performance is the signal-to-noise ratio at the receive antenna port for a specified signal-information bandwidth. The results of the study indicate that, for a new type of efficient antenna, operation at frequencies below 20 MHz has the potential for communications over a set of environments ranging from a benign flat rural terrain to a severe urban environment. Without this new antenna, no one frequency band provides good performance for all environments. This new 'Merenda' antenna is discussed briefly in an appendix. The benefits associated with the use of this antenna are included in the body of the paper.
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