R&S^®CMU300 Universal Radio Communication Tester

GSM/EDGE

Test Modes

• Non-signaling mode

This mode is particularly suitable for testing RF boards/modules with little or no signaling activity. The measurement starts completely independently from external trigger signals or signaling information. As soon as RF power is applied to the input, the tester starts to sample the incoming RF signal. When the corresponding RF parameters are calculated and displayed, the instrument is ready for the next measurement. All GSM/EDGE-specific TX measurements on signals with appropriate modulation scheme and midamble are available. In addition, the CMU300 is able to generate signals with GSM/EDGE-specific midamble and modulation in the entire frequency range from 10 MHz to 2.7 GHz. The analyzer and generator functionalities are not linked, i.e. any channel spacing between uplink and downlink signals is possible.

• Signaling mode

The signaling mode is provided for testing modules or base stations supporting a certain level of signaling. In this mode, the tester operates synchronously to the BTS, i.e. it is synchronized to the TDMA frame structure, which is vital for receiver bit-error-rate measurement. All transmitter parameters can be tested separately for each timeslot. This function is necessary for testing base stations that support both GSM and EDGE. The ability to code / decode channels in realtime is the basis for synchronized measurements. The instrument can be synchronized to the base station in the following ways:

• If the BTS has a multiframe clock out-put, the signal can be used to trigger the CMU300. An additional trigger line has to be taken into considera-tion. For BER tests and EDGE TX tests the 26 multiframe trigger is required.
• If only the RF connection is used, the tester can synchronize to the C0 carrier of the base station, just like a mobile phone. This simplifies the test setup. However, a CCH carrier including FCCH / SCH channels and system information 1 to 4 must be activated in the BTS before measuring the used traffic channel. After successful synchronization there is permanent resynchronization to SACCH of TCH.

Overview TX Test GMSK

Power measurements:

• burst power (average/peak)
• power versus time (power ramp)

Modulation analysis:

• phase error (peak/RMS)
• frequency error

Spectrum measurements:

• spectrum due to modulation
• switching transients spectrum

Additional functionality in signaling Mode:

• power versus slot measurement
• time slot selective measurements
• analysis of CCH information (frame timing; network data)
• analysis of SACCH information (requested power; requested timing)

Overview TX Test 8PSK

Power measurements:

• burst power (average / peak)
• power versus time (power ramp)

Modulation analysis:

• EVM = error vector magnitude (peak / RMS)
• magnitude error (peak / RMS)
• phase error (peak / RMS)
• origin offset
• IQ imbalance
• frequency error
• 95^th percentile

Spectrum measurements:

• spectrum due to modulation
• switching transients spectrum

Additional functionality in Signaling Mode:

• time slot selective measurements
• analysis of CCH information (frame timing; network data)
• analysis of SACCH information (requested power; requested timing)

Overview RX Tests