Chapter 2, Making Measurements

Receiver Performance in Additive Noise

Receiver Performance in Additive Noise

Overview

In this test, the CDMA signal generator is used with the Additive White Gaussian

 

Noise (AWGN) source to simulate an uplink signal to the base stations’s receiver.

 

Various levels of signal-to-noise (Eb/No) can be used and the resulting Frame

 

Error Rate (FER) is measured at each Eb/No level.

EVEN SECOND/

(Rear Panel)

SYNC IN

 

Receiver Port 1

 

H

 

Receiver Port 2

SYNTH

 

REF IN

Even-second

 

Clock

 

Time Base

 

H

 

 

RF IN/OUT

Figure 21

 

 

 

NOTE:

The test procedures outlined in this section require that you have already configured the

 

Test System as outlined in chapter 1, "Getting Started".

 

 

Requirements

• You will need a means of reading the Frame Error Rate (FER) from the base station.

 

The CDMA generator sends a random bit pattern which the base station decodes and

 

uses to calculate FER. Some means of reading the calculated value is required. Often

 

this is done via a laptop PC connected to the station equipment by serial or LAN port.

•This test requires synchronization between the Test System’s CDMA signal generator and the base-station-under-test. This is achieved using the Even-Second clock signal from the base station.

•The CDMA generator should be connected directly to the receiver’s input(s). This can be achieved by connecting to only one input at a time or by using a splitter to connect to both inputs at once (if there is more than one receiver test port).

•You must know the following about your base station and setup:

❒The base station channel number setting.

❒The Receiver PN Offset for the base-station-under-test (typically 0).

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