1999-05-17 Special Called Meeting and Workshop Meeting

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. k Tests Show Metricom's innovative Ricochet service is based on an inter- Metricom Radios connected mesh network architecture that transmits digital Are Well Below packets of data across a wireless network of intelligent "pole - ANSI Standards top" radios attached to buildings, streetlight and utility poles. Typical space between radios is approximately a quarter to a half mile; each radio in the network can originate messages, and send and receive information. 4 Metricom's network poletop radios have undergone testing by an independent third party to ensure that they meet current and proposed RF emission standards. These radios operate at less than one watt of power in two public frequency ranges, 902-928 MHz and 2.4GHz. According to a November, 1998 report by Hammett and Edison I, a certified testing agency, the levels of RF energy emitted by the Metricom radios, in both frequency ranges, were substantially below the permitted lev- els of exposure delineated by ANSI standard C95.1. To determine the maximum ambient RF levels, the Hammett and Edison tests were conducted with the measurement probe actually touching the Metricom network radio's antenna face, much closer than any user or bystander would ever get to a Metricom radio. In fact, Metricom's Ricochet radios are well below the Public Limit set by the FCC. The radios, however, are mounted on poletops at least 25 feet above the ground. At 25 to 100 feet, the typical distance of any Metricom network radio to any person or nearby house, energy emissions are barely measurable (the energy of a radio wave decreases with the distance from the source.)2 1. Metricom, Inc., Dual Band Microcell Radio, Statement of William F. Hammett, Consulting Engineer, November, 1998. 2. See Hammett and Edison, November 1998 Report. With the mea- surement probe touching the antenna face, the maximum ambient RF levels due to the operation of the 2.4 GHz antenna measured 0.135 µW/cm2 which is only 13.5 percent of the applicable public limit for devices operating at 1 watt in the 2.4 GHz range.