ADTRAN 2 x E1 user manual CO-LOCATING Multiple Systems, Antenna Alignment, Rf Low

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61280004L2-1C

Section 2 Installation

CO-LOCATING MULTIPLE SYSTEMS

When multiple transmitters are to be co-located (installed in the same equipment room or on the same tower), it is advised to set all systems as follows:

1.If more than one system in the same frequency band is transmitting from the same location, set the antenna polarity of one system horizontal and the other system(s) vertical. (The antennas should be marked as to which mounting position is vertical or horizontal.) This will provide approximately 30 dB of isolation between the different antennas.

2.If more than one TRACER system is installed, set the co-located transmitters to the same frequency plan (example: Plan A or Plan B) and set each to a different spreading code. This keeps the transmitters on the additional system(s) from interfering with the co-located receiver(s).

3.If the systems are from different manufacturers, set the transmit frequencies as close as possible with different spreading codes. Other manufacturers may not use the exact frequency plans as the TRACER system, but keeping the frequencies close will reduce the probability of the transmitter(s) interfering with the co-located receiver(s).

ANTENNA ALIGNMENT

After the transmitter power for each end has been adjusted and the BBP and RFC have been installed and connected, the antenna should be connected to the RFC via the feedline. Verify that both antennas are arranged on the same polarity: vertical or horizontal. The antennas should be aimed toward one another as precisely as possible and the received signal strength indicator (RSSI) voltage measured. The RSSI voltage is a function of the signal strength at the receiver and is used to measure the received signal strength. RSSI varies approximately from 0 to >4 volts, with 0 volts corresponding to a weaker received signal and 4 volts or better corresponding to a stronger received signal.

NOTE

The voltage level present at the RSSI test point represents a relative signal level of receive strength from the far end. No direct correlation can be made between RSSI voltage level and actual receive level in dBm. This test point is provided to assess relative signal level for alignment of antenna.

RF LOW

The “RF Low” LED indicates that the received signal is within 10dB of the minimum received signal strength (RSL < approximately -80 dBm). If this indicator is on, the link performance may be marginal. The antennas should be peaked in azimuth and elevation until the desired signal level is achieved. RSSI may be monitored on either the RF unit or the front of the BBP. If the received signal is too strong and RSSI reaches a maximum such that the peak cannot be discerned, then the transmitter on the far end should be turned down.

At this point the radio link should be operational. Proper operation can be determined by the status of the “LINK DOWN” LED. If this LED is on, the link is not operational. If this LED is not on, the link is operating. Certain types of interference can cause one end of a path to operate and the other end to fail. In some instances, this may be corrected by swapping the frequency plan at each end, thus avoiding the interference if it is stronger at one end than the other. Changing the spreading code at each end may also allow interference to be mitigated.

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TRACER 2 x E1 User’s Manual

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Contents Tracer 2 x E1 User’s Manual 61280004L2-1C Radio Frequency Interface Statement R N I N GRadio Frequency Interference Statement Table of Contents Operation Troubleshooting Specifications Warranty, Ordering and Return InformationGlossary Appendix aIllustrations Viii Tracer Description IntroductionApplications Spread SpectrumForward Error Correction Tracer DescriptionChannel Selection Direct SequenceBaseband Processor or BBP Tracer System ConfigurationE1 Interfaces Block diagram of the BBP is shown in Figure VT100 RS-232 InterfaceAlarm Contacts If SignalPower Controls and IndicatorsFreq Name Function Non-volatile MemoryBuilt-In Tests Radio Frequency Converter or RFC10. Front and Rear of Rackmount RFC Housing Antenna Selection Antenna 100 mWInstallation UNPACK, InspectInstallation Grounding15 Pin RJ-48 E1 InterfacesLink Planning P O R T a N TAntenna Feedline Loss Antenna GainPath Loss Path AvailabilitySetting the Transmitter Power GHZ, 1 Watt Transmitter OptionSetting the RFC Frequency Plan on NON 1 Watt 2.4 GHZ Models 4 GHz DiplexerPlan a Plan B Setting the RFC Frequency Plan on 5.8 GHZ Models 8 GHz DiplexerConnecting the BBP and the RFC Applying PowerAutomatic BBP Frequency Plan Spreading CodeRF LOW CO-LOCATING Multiple SystemsAntenna Alignment Alarm Contacts Remote BertInstallation Password OperationVT100 User Interface RS-232 InterfaceSystem Status Screen OperationMain Menu Selections Main Menu Screen Tracer Main MenuE1 Status / Configuration / Loopback E1A Status ScreenLink Performance History Link Performance History ScreenE1A Statistics E1B StatisticsSectionTROUBLESHOOTING4 Troubleshooting Problem Descriptions and Recommended ActionsTroubleshooting Using the Front Panel Indicators GeneralRecommended Actions TroubleshootingCV/CRC Light on E1A or E1B is Lit when CRC is enabled LBK-A or LBK-B is Lit LOS/OOF Light on E1A or E1BNo Power Light ALM is LitTest Light is Lit or Blinking TST Light is Lit After Pressing Remote Test ButtonFail Light is Lit After Pressing Remote Test Button RF Low Light is OnCV Alarm Troubleshooting Using the VT100 User InterfaceLOS Alarm RMT Alarm OOF AlarmCRC Alarm UA1 Alarm Code Sync Status Carrier Sync Status or E1 Mux Sync Status ES Values in E1A or E1B Performance History Menu Possible CauseRFC Link Up Status SES Values in E1A or E1B Performance History Menu Troubleshooting Specifications Specifications PowerVT100 Terminal Interface Mechanical & EnvironmentalWARRANTY, Ordering and Return WarrantySales Repairs and ReturnsWarranty, Ordering and Return Information Glossary Acronyms Used in this ManualGlossary Appendix a Cable Connections Terminal Connection DB-25Personal Computer Connection DB-9 Modem Connection DB-25Appendix a Cable Connections
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