Specifications

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After setting up the equipment, the ESG Option 201 system is configured
as discussed earlier in section 3 of this document. At this point, a signal
will be present at the ESG’s RF output. The signal generated by the ESG
will appear to the mobile phone as a basestation signal. It is the phone’s
duty, at this point, to synchronize to the signal and read the overhead
channels. The synchronization process consists of the following steps:
1) Mobile receiver acquires the ESG Pilot
2) Mobile receiver acquires and decodes the Sync channel
3) Mobile receiver acquires and monitors the Paging channel
After synchronization has been completed, the phone is placed in test
mode and test mode commands are issued by the user. The mobile
receiver is instructed, via test mode, to listen for a specific RC traffic
channel on a specific Walsh code (e.g. RC2, F-FCH, Walsh code 47).
The mobile set then begins decoding the specified traffic channel and is
requested, once again via test mode, to report the number of frames in
error.
Once this general measurement procedure has been established, the
various FER tests may be performed.
Sensitivity and dynamic range
The sensitivity measurement provides the minimum power level at the
receiver that results in a FER, which does not exceed a specified value.
For example, the test would determine the power level required to
achieve less than 0.5% FER. Sensitivity helps characterize a receiver’s
ability to demodulate a low-level signal. Sensitivity is a key measure of
merit in receiver design because a receiver that has higher sensitivity will
receive signals more accurately and require less power from the basesta-
tion.
Similarly, the receiver’s dynamic range is the input power range over
which the FER does not exceed a specific value.
Adjacent channel interference
The adjacent channel interference FER test is a variation on sensitivity in
which the sensitivity of the receiver is measured in the presence of an
adjacent channel signal.
Fading and multi-path distortions
In this test, fading and multi-path distortions are applied to the signal
source and the sensitivity of the receiver is measured under varying
distortion conditions. A channel simulator is used to induce the fading
and multi-path distortions. This test is very critical for receiver design
since fading and multi-path are major obstacles which real-life receivers
must overcome.
Single tone desensitization
This test measures the ability of the receiver to receive a signal in the
presence of a single tone at a given frequency offset away from its center
frequency. FER provides the measure of merit.
This test is important because it determines the receiver’s ability to
resolve its signal in the presence of an interfering tone.
Test Mode
In order to perform the tests
defined herein, the mobile device is
required to have a test mode which
will allow it to deviate from the
normal handshaking requirements
and go into a manual control
mode. The mobile device can then
be controlled by a computer.