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CTA Communications <br />Orange RaCE Test Report <br />and then initiates a talk -out message. The talk -out message is received at the mobile <br />unit, recorded, and analyzed. The location of the talk -out DAQ measurement is <br />established as the latitude and longitude of the mobile unit when the talk out message <br />began. In this manner, both paths (talk -in and talk -out) are evaluated in RaCE testing. <br />5.5.2 Passed /Failed DAQ Test Sample <br />A passed test sample is one in which a message is received and equal to or exceeds the <br />established DAQ threshold value. A failed test sample is one in which a test sample <br />message is initiated and either no reply message is received within the test timeout or the <br />received message is below the established DAQ threshold value. Test sample result <br />locations are established based on the location of the mobile at the start of the test <br />message. Regardless of the pass or fail result, the actual audio file is retained as part of <br />the test file both for after - the -fact confirmation, and also for any future analysis that might <br />be indicated. <br />5.5.3 Received Signal Strength Indicator (RSSI) Test Samples <br />Received Signal Strength Indicator (or Indication): A measurement in dBm that <br />represents the strength of the incoming (received) signal in a receiver. <br />The mobile test unit has two additional auxiliary receivers and antennas to perform RSSI <br />measurements. During testing, the RSSI receivers scan through the stored frequency <br />table and collect samples based upon the analog -to- digital conversion of the voltage <br />present on the automatic gain control line from the receiver. These samples are <br />collected continuously except during the talk -in DAQ test transmission. Ten samples are <br />collected per frequency at an average rate of 57 samples per second and then the <br />receiver scans to the next frequency. The receivers have been programmed to allow 50 <br />milliseconds to tune to the next frequency on the scan list and settle before beginning the <br />series of RSSI measurements at the new frequency. See FIGURE 5 -1 below. The <br />dynamic range of the ICOM receiver is -55 dBm to -120 dBm with a 1 dB resolution. The <br />median value of a frequency's samples that were collected during the talk -out message is <br />used for analysis and display. This data was post - processed and included in the test <br />results section of this report. <br />f, 1 f, 3 f, 9 f21 f2 3 f29 <br />♦ f12 . * f, 10 f f2 2 , f f210 <br />•• •I I 1 1 1 0 0 0 <br />Sec <br />50 msec <br />5.5.4 Passed /Failed RSSI Test Sample <br />A passed RSSI test sample is one in which the recorded signal level of the sample is <br />equal to or exceeds the established CPC threshold. A failed RSSI test sample is one in <br />which the recorded signal level of the sample is below the established CPC threshold. <br />Test sample result locations are established based on the location of the mobile at the <br />start of the test message. <br />-11 - HSMM I , t 1 <br />