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CTA C®imunications <br />Orange RaCE Test Report <br />Both talk-in and talk-out directions must be adjusted to account for the differences in <br />gain/losses between these two different configurations. Different attenuation factors for <br />talk-out and talk-in are achieved by using a circulator in the RaCE mobile unit antenna <br />feed line as shown in FIGURE 6-2. The values for the attenuators are shown in this <br />figure and calculated as follows. <br />In the RaCE mobile unit talk-out direction, attenuation is needed to account for the <br />difference in receive sensitivity of the test mobile and the receiver sensitivity of the typical <br />portable, as well as the difference in the antenna losses for these two different <br />configurations. We first select the amount of attenuation (Attenuator #1) needed to <br />simulate the corrected talk-out attenuation required. This value is calculated to be 6.5 dB <br />and a commonly available 6 dB attenuator was used for this purpose. The loss through <br />the circulator of approximately 0.6 dB is factored into the calculations, and the test set-up <br />talk-out correction is calculated to be 6.6 dB including the loss for the circulator. TABLE <br />6-4 summarizes the calculation of attenuation needed for the RaCE mobile unit talk-out <br />correction to simulate the typical portable operational configuration. <br />The next step is to calculate the attenuation needed for the RaCE mobile unit talk-in <br />correction, taking into consideration the difference in test mobile transmitter power and <br />typical portable transmitter power, as well as the difference in antenna system losses <br />between these two configurations. This value was calculated to be 15.7 dB. As shown in <br />FIGURE 6-2, this is comprised of the series of Attenuators #1, Attenuator #2 and the <br />circulator. An additional 9.1 d6 of attenuation is needed and two commonly available <br />attenuators totaling 9.3 dB of attenuation was utilized. TABLE 6-5 summarizes the <br />calculation of the attenuation needed for the RaCE mobile unit talk-in correction to <br />simulate the typical portable operational configuration. <br />Mobile Unit Talk-Out Correction <br />Receiver Sensitivity <br />Portable <br />Mobile <br />Antenna System Losses <br />Portable Talk-Out Antenna System <br />Total for at the Hip <br />Mobile Talk-Out Antenna System <br />Mobile Antenna <br />Mobile Coax <br />Circulator <br />Total for Mobile Talk-Out Antenna <br />r Portable Receive <br />-119.0 dB <br />-119.0 dB <br />Sensitivity Difference -0 d6 <br />9.0 dB <br />0.0 d6 <br />1.9 d6 <br />0.6 d6 _ <br />2.5 dB <br />Antenna System Loss Difference 6.5 dB <br />Total Talk-Out Correction Attenuation 6.5 d6 <br />Test Set-Up Talk-Out Attenuation (per FIGURE 3-2) _ <br />(Attenuator #1 + Circulator) <br />Attenuator #1 selected to be 6 dB <br />Test Set-Up Talk-Out Attenuation is (Attenuator #1 + Circulator) 6.6 dB <br /> <br />