Chapter 2, Making Measurements
Modulation Quality (Rho)
Modulation Quality (Rho)Overview | In this measurement, the modulated signal is compared to an ideal, reference | |
| waveform to determine the performance of the transmitter’s modulation circuitry. | |
| Rho values are in the range of 0 to 1. A value of 1 indicates perfect correlation to | |
| the reference (high modulation quality). CDMA base station standards require | |
| that transmitters have rho performance of 0.912 or higher. |
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| EVEN SECOND/ | (Rear Panel) |
| SYNC IN |
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| H |
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| Transmitter Port | SYNTH |
| REF IN | |
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| Clock |
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| Time Base |
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| H |
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| RF IN/OUT |
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Figure 8
CAUTION:
NOTE:
Requirements
Before performing any transmitter measurements, make sure that the power level applied to the RF IN/OUT port of the PCS Interface does not exceed the published limit. For CDMA base station signals this is 1 Watt (+30 dBm). You may have to use an external attenuator or directional coupler, depending on the power output for your transmitter. Signal levels greater than the specified maximum can cause damage to the test equipment.
The test procedures outlined in this section require that you have already configured the Test System as outlined in chapter 1, "Getting Started".
•Synchronization is required, so you must have an
•You must have the ability to transmit the pilot channel only (Walsh 0).
•You must know the following about the base station and setup:
❒The base station channel number setting.
❒The PN Offset for the
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