Anritsu 3GPP, Руководство по измерениям

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3GPP MG PN: 10580-00234 Rev. Y 2-1
Chapter 2 — GSM/GPRS/EDGE
Signal Analyzer
2-1 Introduction
The Global Systems for Mobile (GSM) communication is a globally accepted standard for
digital cellular communication. GSM uses a combination of Frequency Division Multiple
Access (FDMA) and Time Division Multiple Access (TDMA). Within each band are
approximately one hundred available carrier frequencies on 200 kHz spacing (FDMA), and
each carrier is broken up into time-slots so as to support eight separate conversations
(TDMA). Each channel has an uplink and a downlink. GSM uses the Gaussian Minimum
Shift Keying (GMSK) modulation method.
GPRS/EDGE is an extension of GSM technology and is applicable to data services. GSM uses
Gaussian Minimum Shift Keying (GMSK) modulation and EGDE uses 8PSK Phase Shift
Keying modulation.
The GSM/GPRS/EDGE frequency ranges are: 380–400 MHz, 410–430 MHz, 450–468 MHz,
478–496 MHz, 698–746 MHz, 747–792 MHz, 806–866 MHz, 824–894 MHz, 890–960 MHz,
880–960 MHz, 876–960 MHz, 870–921 MHz, and 1710–1990 MHz.
The instrument features two GSM/GPRS/EDGE measurement modes: RF Measurements and
Demodulator. The instrument can be directly connected to any GSM/GPRS/EDGE base
station for accurate measurements. When a physical connection is not available or required,
the instrument can receive and demodulate GSM/GPRS/EDGE signals over the air.
GSM/GPRS/EDGE RF measurements provide views of spectrum, power versus time (frame),
power versus time (slot) with mask and summary screens.
The spectrum view displays channel spectrum and multi-channel spectrum. The channel
spectrum screen includes channel power, burst power, average burst power, frequency error,
modulation type, and Base Station Identity Code (BSIC). The multi-channel spectrum
displays as many as ten channels and, using the cursor to select a channel, can display the
measurements for just the selected channel.
GSM/GPRS/EDGE Demodulator demodulates GSM/GPRS/EDGE signals and displays the
results of detailed measurements to analyze transmitter modulation performance. Results
are shown for phase error (rms), phase error peak, EVM (rms), EVM (peak), origin offset, C/I,
modulation type and magnitude error (rms) and a vector diagram of the signal.
This chapter describes the menus in GSM/GPRS/EDGE Signal Analyzer mode.
Note
Screen capture images are provided as examples. The image and measurement
details shown on your instrument may differ from the examples in this
measurement guide.