Testing Motorola DMR MOTOTRBO Radios with the Cobham 3920B Radio Test Platform

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1 Application Note Testing Motorola DMR MOTOTRBO Radios with the Cobham 3920B Radio Test Platform The Cobham 3920B is the complete tool for anyone wishing to test Analog or Digital MOTOTRBO mobile or portable radios. In the DMR mode, this flexible test set allows testing of the major on-channel transmitter measurements, while also providing valid test patterns to check receiver senitivity.

2 Introduction The 3920B is a Radio Test Solution from Cobham AvComm for engineering, production and field service applications. The instrument provides a comprehensive range of general purpose analog measurement facilities as well as advanced digital test options for P25, TETRA, HPD, NXDN, dpmr, DMR, and ARIB T98 systems. Standard features include: Full AM, FM and SSB test capabilities 5 MHz channel spectrum analyzer Full Span spectrum analyzer to 2.7 GHz (with option 392XOPT058) Dual-Channel oscilloscope to 4 MHz Full audio analysis for AF level, frequency, SINAD and distortion measurements Full RF parametric tests for power, frequency error, deviation (FM) and modulation index (AM) Three high accuracy audio modulators/function generators Three high accuracy audio baseband generators DTMF and DCS generators DTMF and DCS decode Encode and decode of tone remote, two tone sequential and 5/6 tone formats Variable notch SINAD, distortion and SNR meters Color coded Pass/Fail meter functions for fast test capabilities Accurate broadband and in-band power meters The digital architecture of the 3920B delivers faster, accurate and more repeatable measurements than any of its predecessors and provides for future technology enhancements as new digital technology becomes available. Combining the power of an onboard PC with a 30 DB hard-drive and Linux OS, the 3920B also supports USB mouse and keyboard interface for very easy operation as well as almost unlimited save/recall setups, saving time and effort. The 3920B features easy to read meters with Pass/Fail color coding for instant Go/NoGo testing. With these easy to configure meters, the user can set up unique Pass/Fail parameters for each radio type that is being tested. When used with the save/recall locations, this allows for instant recall of the test parameters so semi-technical or non-technical individuals can simply key the radio and test. The meter will display Green for good, Red for high and Blue for low. A quick glance and the operator will know that the radio is within established test parameters. DMR Testing - Manual Mode Ability to receive, demodulate and analyze DMR modulated signals Ability to perform RF and modulation parametric tests on the Unit Under Test (UUT) Distribution, Constellation and Eye Diagram graph plots Variety of UUT measurements including Bit Error Rate, Signal Power, Slot Power, Frequency Error, Symbol Clock Error, Symbol Deviation, and FSK Error Prower Profile Over Time, Profile Full and Profile Ramps Display Tiles Spectrum Analyzer, Channel Analyzer and Oscillloscope available within the DMR Test System Testing Motorola MOTOTRBO DMR Radios This document wil go step-by-step through the setting up the 3920B to test Motorola DMR radios. Test Requirements - The Cobham 3920B Series Digital Radio Test Set (3901, 3902, or 3920) with software version or above - The 390XOPT400 DMR software option for the 3920B - A Motorola MOTOTRBO radio, when possible with configuration software CPS and alignment, testing software Tuner and programming cable PMKN4012B. Motorola CPS: Motorola mobile and portable radios are packed with user friendly features that can be activated through Customer Programming Software (CPS). CPS is a vital component of the overall system operation, and is a full feature tool that enables you to program all available radio features, but most importantly, the radio personality. Option 390XOPT400 adds advanced testing capability for DMR (Digital Mobile Radio). This option enables the Cobham 3920B Series Digital Radio Test Set to test and align a wide range of DMR radios. DMR radio technology is a new digital radio format offering advanced communications features specified by the ETSI technical standard DMR technology is currently under development or being released by a number of OEM radio manufacturers, and includes Motorola s new MOTOTRBO technology. DMR Option Overview The 3920B DMR Test System Option provides the user with the following capabilities: Ability to support Simplex, Half Duplex radio modes Ability to generate DMR test patterns for receiver sensitivity measurements Ability to Code and Decode Color Code, Call ID and User ID Testing in Analog Mode Only Most Motorola MOTOTRBO DMR radios can be configured with channels in Analog or Digital modes. The 3920B standard Analog Duplex capabilities can be used to fully test Analog Tx and Rx functions. Refer to the 3920B Operation

3 Manual or Online Courseware for more details about Analog Testing. Note: to make Analog measurements even more user friendly, most Analog FM test capabilities can be found in the DMR standard mode tiles (see below). Configure test limits by pressing the Configuration key and selecting the UUT Measurements Limits Configuration Tile. Testing in Digital Mode To enter DMR mode in the 3920B, select DMR in the Configuration Tile to obtain the display below in Test Mode, Manual Tiled. Enter the offset of the connection cable in the Offset Configuration Tile to ensure accurate power measurements. Test in Simplex Single Frequency Mode Mobile Radio Transmitter Test: Step 1: configure mobile. Turn on the radio. Select a valid digital channel single frequency. Step 2: configure Test Set In the RF Control Tile, enter the channel frequency (if not known use the Spectrum Analyzer mode and key up the radio to find the Tx Frequency). Select T/R in the RF In soft key. Mobile Radio Transmitter Test Step 3: make TX measurement. Connect the radio to the T/R port. Key the radio PTT. Step 4: select the measurement displays The four tiles, below the RF control can be configured to display the Tx numeric or graphic measurements. Note that all numeric measurements can

4 be made against limits (if enabled) and show a corresponding color code. Select the measurements windows using the drop down key. All windows have a large or small version to be selected on the top left hand corner. The following windows are available: Decode Tile: decodes the Color Code, Call ID and User ID of the UUT. Open Tuner Tx BER window, select the Test pattern (1031 for example) and key the radio (PTT toggle). Configure 3920B UUT measurement window with the same Test pattern and read the BER measurement result. UUT Measurements Tile: Six measurements to be chosen in the list, Broadband Power, Frequency Error, Magnitude Error, FSK Error, Signal Power, Slot Power Ratio, Slot 1/Slot 2 Power, Symbol Clock Error, Symbol Deviation, UUT Tx Bit Error. The following other patterns can be selected: Silence or (std IB 511 on the 3920B). Note the Std IB Cal is a IB511 pattern with about 1% error. Advanced Analysis Tile: gives a quick view of the most important measurements. UUT Tx Bit Error: for such a measurement you need to control the radio with the Motorola Tuner Software and put it in the Tx BER mode.

5 Enabling UUT Measurement limits in the Config menu will allow quick color view of the pass/file values. Power Profile Tiles: display the profile of the signal s power reading over a period of time, the FULL profile or the RAMPS. Constellation Tile: represent the four deviation states of the FSK modulation (in green the expected positions). Eye Diagram Tile: used to plot the demodulated signal from one slot of the DMR signal. Channel Analyzer Tile: display the signal spectrum but not synchronized with the burst. The Max hold function will give the spectrum shape. Distribution Tile: shows the relative number of symbols in relation to each other.

6 Mobile Radio Receiver Test Two types of test can be performed on the MOTOTRBO Radio RX, a voice/ audio quality test and a BER sensitivity test (together with Motorola Tuner software). Audio/Voice Quality Test: RX BER Sensitivity Test: Step 1: configure the test set In the RF Control Tile, enter the channel frequency in the Transmit Tile and start with a level of -80 dbm for instance. Select the test pattern STD IB 1031 for IB511. Step 1: configure the test set. In the RF Control Tile, enter the channel frequency in the Transmit Tile and start with a level of -80 dbm for instance. Select the test pattern STD IB 1031 and enter a Color Code and Call ID supported by the radio to be tested. Turn RF Gen ON. Step 2: connect the radio to the T/R port. Turn RF Gen ON. Step 2: connect the radio to the T/R port. Step 3: Open Tuner RX BER window, select the Test pattern corresponding to the 3920B Generator configuration (0.153 for example) and start the BER measurement. You should now hear the 1 khz digital test tone in the radio s loudspeaker. Step 3: test the RX audio quality/sensitivity. Go back in the RF Control Tile and decrease the RF level until you hear the 1 khz tone deteriorate or disappear. This should occur below -120 dbm and will give you a good idea of the receiver sensitivity. Note: the khz pattern can be replaced by a pre-recorded speech (stored SPCH patter) or by external audio or voice (using audio or microphone inputs). See next 3920B display for configuration details.

7 Step 4: measure the RX BER sensitivity. Go back in the RF Control Tile of the 3920B and decrease the RF level until the BER starts to grow. A 1% BER should occur around -120 dbm. Note: to check the radio ability to measure the BER correctly you can use the 3920B std IB CAL pattern at a normal level (-80 dbm for example) and verify the Tuner reported BER is 1%. Step 4: select the measurement displays the same way you would do it in the simplex mode. Step 5: check the RX audio/speech quality. Test in Half Duplex Offset Frequency Mode Mobile Radio Transmitter and Receiver Tests: In the RF Control Tile, select the test pattern STD IB 1031 or Voice/Stored SPCH and start with a level of -80 dbm for instance. You should hear the 1 khz digital test tone or voice/speech and can test the sensitivity by decreasing the RF level. Step 1: configure mobile. Turn on the radio. Select a valid digital channel offset frequency. Connect the radio to the T/R port Step 2: configure the Test Set. In the RF Control Tile, enter the channel transmit and receive frequencies or Tx frequency and Rx offset. Select the pattern STD OB TSYNC. This allows a radio programmed with a transmit offset to synchronize with an Outbound channel and transmit back on an offset channel. Check that the CC is supported by the radio or change it. Select T/R in the RF In or RF Out soft keys. DMR Testing: Automated Mode The Cobham OPtion 390XOPT610 Automated Test and Alignment procedure provides fully automated test and alignment of MOTOTRBO portable radios without the need for user interaction. This test system ensures consistent and reliable tests and alignment to manufacturer recommended specifications and to industry standards, ensuring proper interoperability and a uniform standard of performance within the radio s network technology. Configure test limits and cable offsets as previously for the simplex mode. Turn RF Gen ON. Step 3: make measurements. Key the radio PTT. Select the Tx measurement windows as for simplex mode. In case you cannot see any measurements, check the 3920B configuration as the radio may not see the outbound signal. Test Requirements: - Aeroflex 3920B Digital Radio Test Platform (3901, 3902 or 3920) with software version or above XOPT400 DMR Software, OPT401 Auto-Test II for DMR and OPT601 for MOTOTRBO Test software - A Motorola MOTOTRBO radio programming cable PMKN4012B

8 Step 1: connect the radio. Turn on the radio. Connect the radio antenna port to the T/R port. Connect the programming cable to a 3920B USB port. Step 2: configure the Test Set. Load the Auto-Test mode and select the Motorola MOTOTRBO Auto-Test script. Note: cable offset can be entered as a fixed value or as a table calculated using the Cable Loss wizard. Step 3: select tests to be performed with corresponding tick boxes. Note: some analog tests also need the Motorola audio breakout box model RLN4660. Step 4: select Test or Align soft keys to perfom test only or re-alignment of failed parameters. Press the Read radio soft key to determine the radio type and give access to the test modes. Step 5: at the end of test press continue to either: - Save or print test results. - Start a new test or align process. Press the Edit Specs soft key to check the radio model, test specifications, enter the RF cable offset and add some user information. Test Summary Display

9 Test Results Display Alignment Results Display Test results are saved in a text file, on the internal hard drive or on a USB key with a file name including radio model, serial numbers, and time stamp (H55QDH9JA1AN-037TKN txt). The 3920B Series Digital Radio Test Platform The 3920B Series is the next generation portable test set platform for advanced professional digital radio communications. Building upon a long-standing reputation for excellence in professional radio communication test, the 3920B Series from Cobham sets a new benchmark for quality, ease of use, performance, and value. For more information on the Cobham 3920B Series Products mentioned in this Application Note, do not hesitate to visit our web site: avcomm. And particularly the 3920B product page: Part No. 2000APP-1, Issue 1, 06/16