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CTA Communications <br />Orange RaCE Test Report <br />7.0 Test Method <br />7.1 RaCE Test System Capabilities and Characteristics <br />RaCE coverage tests were conducted both in the "talk -in" and "talk -out" directions using <br />radios designed to operate in the system under test. The results from these tests are <br />correlated in a post - processing step to allow presentation on a detailed map of the test <br />area. Received signal strength (RSSI) information was also gathered for the control <br />channels of other IWN radio sites as the mobile traversed the test area. All of the tests <br />were conducted in the continuous by time mode. Each measurement was tagged with <br />position and time information derived from a GPS receiver attached to the mobile unit. <br />This allows for the accurate display of the test locations as well as the correct correlation <br />of "talk -in" to "talk -out" results. <br />7.1.1 Talk -In and Talk -Out DAQ Testing <br />In talk -in and talk -out DAQ testing, the mobile unit initiates the test by sending a test <br />message and the stationary unit responds with the same test message. A minimum <br />mobile speed of 5 mph was set to initiate the test in order to include the effects of multi - <br />path fading. The mobile unit operates the PTT line and waits for a transmit power sensor <br />"TX" condition lasting for at least 0.5 seconds. This can only occur if a channel grant has <br />been obtained in trunking systems and assures the availability of a talk path through the <br />system. The test message is then sent to the transmitter followed by a return to the <br />receive condition. At the stationary unit, the test message is recorded and permanently <br />stored together with a time stamp. The time stamp is used in post - processing to <br />correlate the actions of the two units in order to display the transmit position of the mobile <br />unit. The stationary unit then generates a new test message and sends it out to the <br />mobile unit while keeping track of the time sent. <br />The mobile unit receives and stores the message along with the position and time stamp. <br />The message is then analyzed for DAQ. A color code is assigned to the tested position <br />on the operator's map indicating the DAQ as seen by the mobile. The mobile then waits <br />until the proper time has elapsed before repeating the process. <br />7.1.2 RSSI Test Mode <br />The RSSI Test Mode is used for received signal strength recording during the DAQ Test <br />Mode or it may be used as a standalone test. The recording of RSSI will show the <br />received signal level in dBm during the receive portion of the DAQ test using the same <br />time and position. A minimum speed of 5 miles /hour is imposed on the start of each data <br />gathering period to prevent long periods of data when the vehicle is stopped as well as to <br />average out multi -path fading effects. <br />-21- H MM I . ECO <br />