Cisco Systems BTS-R3 Broadband Data BTS User Manual chpt 2c 40 00047 04 F I C TTA

Cisco Systems, Inc Broadband Data BTS chpt 2c 40 00047 04 F I C TTA

Manual 4

Navini Networks, Inc. Ripwave Base Station I&C Guide Chapter 2c Part #40-00047-04 Rev F v1.0 (TTA) 61 October 23, 2003 Install the RFS Check all regulatory standards (refer to Chapter 1, Page 8 “Regulatory Information”) prior to installation. Now that the BTS is in place, the RFS is readied for installation. Follow the Panel or Omni Antenna information and procedures below. Reference the specifications in Appendix H. Panel Antenna The RFS Panel antenna is installed on a structure, such as a tower or a pole, which is defined in the site survey and design. Following are the steps to complete the installation of the panel antenna. Verify RFS Operation Verify proper operation of the RFS before installation. Test the transmit and receive path of each antenna in the RFS per Appendix S, and using the RFS System Test Form in Appendix O. Set the Downtilt Check the engineering study for the required downtilt of the antenna. The panel antenna has 6o of fixed electrical downtilt but it can be mechanically adjusted for an uptilt of 0 to 10o. As a result, the main lobe of the beam can be pointed between 4 degrees above and 6 degrees below the horizon. Figure 28: Panel Antenna Elements WeatherizedconnectorsMounting Bracket (downtilt adjustment)WeatherizedconnectorsMounting Bracket (downtilt adjustment)
Ripwave Base Station I&C Guide Navini Networks, Inc. Chapter 2c 62 Part #40-00047-04 Rev F v1.0 (TTA) October 23, 2003 Omni Antenna An Omni antenna has 2 degrees of fixed electrical downtilt Figure 29: Omni Antenna Elements Set the Azimuth Position the RFS on the mounting pole or structure, ensuring that the antenna is pointing in the proper azimuth direction determined by the engineering study. For an omni, the first antenna element must face East (Figure 30). Figure 30: Bottom of an Omni Antenna Showing Correct Orientation Make sure thatthis arrowpoints due East Make sure thatthis arrowpoints due East WeatherizedconnectorsMountingbracketGroundCable HoistWeatherizedconnectorsMountingbracketGroundCable Hoist
Navini Networks, Inc. Ripwave Base Station I&C Guide Chapter 2c Part #40-00047-04 Rev F v1.0 (TTA) 63 October 23, 2003 The azimuth direction is stated in degrees from true North. Use the diagram shown in Figure 31 to determine the declination angle for your location. Add or subtract the declination angle from magnetic North to obtain true North. Tighten the four nuts on each of the two antenna mounting brackets to secure the RFS to the mounting pole. Use a compass to check the direction from the center of the panel (this is magnetic North). Be sure that you are using a compass calibrated for the geographical region where you are. There are five such regions and a compass calibrated for one of them will not work properly in the others. Figure 31: Declination Angle in Degrees (Year 2000) Since this is not the year 2000 anymore, you will want to check this reference map to learn how your magnetic declination shifts from year to year. Notice that the map measures annual shifts in minutes. Since it takes 60 minutes to equal 1 degree, if you notice that your location has a declination shift of 5 minutes per year, this means it will be another 12 years before your declination adjustment changes by one whole degree. The following web site provides more details on how to use these charts: http://www.thecompassstore.com/decvar.html Figure 31a: Annual Change in Magnetic Declination
Ripwave Base Station I&C Guide Navini Networks, Inc. Chapter 2c 64 Part #40-00047-04 Rev F v1.0 (TTA) October 23, 2003 Verify the Downtilt Using an inclinometer (Figure 32), check the downtilt of the RFS antenna. If required, adjust the angle using the downtilt adjustment brackets. Be sure to include any electrical uptilt or downtilt built into the antenna in the setting. Tighten the mounting hardware to secure the RFS in the proper position. Recheck the downtilt angle again to verify proper position. Repeat the procedure for all other antennas that are installed in the system. Ensure that they are mounted in the proper direction and with the correct downtilt angle. Figure 32: Measuring Antenna Downtilt Install Surge Protectors If lightning protection is required, as determined by the customer, the power/data lightning arrestors must comply with UL497. Cables, such as the RF and power/data cables, in excess of 140 feet in length must have protective devices installed that are UL497A or UL497B listed. For accurate results, align the inclinometer against the metal frame on the side of the panel antenna, which is guaranteed to be parallel to the antenna elementsFor accurate results, align the inclinometer against the metal frame on the side of the panel antenna, which is guaranteed to be parallel to the antenna elements

Navigation menu