WILLTEK 4400 Mobile Phone Tester Series, Руководство пользователя

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Chapter 6 Tools
Utilities
4460 GSM System Option and 4468 EDGE System Option Version 12.20
227
In GSM, the measurement and display range covers a complete TDMA frame from
the start of a downlink frame. With a traffic channel active on time slot 3 and
an offset of three time slots between downlink and uplink, the highest current
level can be expected at (3+3) * 0.54738 ms = 3.28 ms.
Other current peaks may result from an active receive/demodulation process.
In the measurement example above, a period of low current can be identified in
the beginning. After 1 ms, the mobile phone sets up its receiver for reception of
the downlink slot. From 1.8 ms to 3 ms, the demodulated data are decoded, and
the transmitter prepares for the uplink slot. Transmission of the uplink slot
follows, requiring a lot of current from the mobile phone; the absolute value
depends on the selected uplink power level. The final phase of the frame is char-
acterized by preparations for the next uplink slot transmission, for example
interleaving in the channel coder.
Understanding the result fields
The difference between current, minimum, maximum and average values is
explained in section
“Statistical data evaluation” on page 242 .
Power — This field shows the average power drawn from the simulated battery,
measured in mW. It is calculated from the selected supply voltage and the
measured current.
Current — The Current Measurement Option measures the current that the
mobile draws from the MS Power Supply outlet. The result is averaged over one
TDMA frame and displayed in mA.
Peak c. — This field indicates the maximum current that has been detected
during the last TDMA frame. The peak current result is shown in mA.
Changing the RF parameters
While measuring the current consumption, you can also switch the RF channel
or the transmitted RF power to evaluate the current consumption under different
parameter settings.
Use the input fields TCH to change to a different channel.
Use the MS scroll field to change the transmit power level.