REI manual MDC-2100/MDC-900, Selecting A Signal With The Mdc Oscor

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Figure 8: SELECTING A SIGNAL WITH THE MDC (OSCOR 4.0)

Version 4

27 Feb 08

the F4 button to further analyze the signal, it is possible to analyze which antenna and filter that is actually receiving the signal. Figure 9 shows the proper antenna selected and the proper filter selected which corrects the signal shape. Furthermore, the unusual signal shape of Figure 8 indicates that this signal should be a Filter B signal.

Note: The OSCOR 5.0 software will not allow this type signal to be displayed.

The frequency span limits are always between 0 and 3GHz. This is because the OSCOR is a spectrum analyzer that covers the frequency range up to 3GHz, but the input frequencies of the down-converter cover 3 to 21GHz (MDC-2100) or 3 to 9 GHz (MDC- 900). Therefore, the cursor frequencies provide the possible signal frequencies while the span numbers (indicated at the top right and left of the display) provide the frequency span the OSCOR is actually viewing after the down-conversion process.

Technical Note: It is possible to have a very slight shift in frequency in the down- conversion process. In the example below, the signal shifted about 50KHz; this is a minimal shift considering the signal is at 10GHz.

Figure 8: SELECTING A SIGNAL WITH THE MDC (OSCOR 4.0)

Technical Note: You may see false signals at 8.5 and 9GHz. These are produced by an interaction of the MDC and the OSCOR. You may minimize this by moving the MDC a few feet from the OSCOR and orientating the MDC metal housing towards the OSCOR.

REI

MDC-2100/MDC-900

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Contents MDC-900 MDC-2100 MDC-2100/MDC-900OWNER’S GUIDE RESEARCH ELECTRONICS INTERNATIONAL 455 Security DriveTABLE of FIGURES TABLE of CONTENTSSTORING A SIGNAL IN THE MDC FREQUENCY RANGE FIGURE 11 ANALYZE MODE USING THE MDC OSCORFigure 1 MDC-2100 MICROWAVE DOWNCONVERTER INTRODUCTIONFilter A ANTENNA BANDFilter B Filter A & BInstalling the MDC-2100/MDC-900 Signal identification Process Operational Control of the MDC-2100/MDC-900OSCOR Version Press F4/MDC Anlz Viewing Bands 1, 2 andPress SWEEP/ANALYZE Press F4/Identify see Figure 6BFigure 6A ANALYZING AN MDC SIGNAL OSCOR OSCOR Sweep and Analyze Modes with the MDCFigure 6B ANALYZING AN MDC SIGNAL OSCOR FIGURE 7 USING “IDENTIFY” TO VERIFY A SIGNAL OSCORFigure 8 SELECTING A SIGNAL WITH THE MDC OSCOR Storing a Sweep Span with the MDC Example of a Desired Frequency Storing a Signal in the MDC Frequency RangeRecommended Implementation SpanMicrowave Transmission Considerations for the MDC it is absolutely necessary in order to save time. A good rule of thumb is to assume that the MDC has an antenna pattern that is about 100 degrees wide. In other words, it is necessary to point the MDC in at least 4 different directions around the room to cover the perimeter. Also, the MDC should be pointed up and possibly moved around the room to cover the ceiling, and down to cover the floor. Furthermore, if you expect a very sophisticated threat, it is recommended to point the MDC into ducting, above ceiling tiles, and in any enclosed spaces in which it would be possible to place a transmitter with a high gain antenna. It is highly recommended that the “Show All” mode of operation for the MDC-2100 be utilized MDCA-all and MDCB-all if using OSCOR 5.0. When a signal is detected, the user can then manually select the different antenna bands and filters to further investigate the signal. Or, the user can simply go to the analyze mode and allow the MDC to determine the operational frequency of the transmitter. Also, it is not recommended to use the MDC with the OSCOR automatic mode unless the MDC directional characteristics are taken into consideration. If running the OSCOR and MDC in the automatic mode, take care to enable the appropriate MDC spans. To maximize usage of the MDC, include MDC 3-21GHz Filter A and MDC 3-21GHz Filter B in your span list For OSCOR 4.0 users, set span to All Bands A&B Using the MTU-2100 Microwave Test Unit Specifications MDC-2100/MDC-900 SPECIFICATIONSMDC-2100 MDC-900Technical Bulletin