ADTRAN 6000 Series system manual Antenna Information, Antenna Alignment, Tracer Rssi Test Points

Section 2 Microwave Path Engineering Basics TRACER 6000 Series Integrated System Manual

6.ANTENNA INFORMATION

The overall wireless system is directly affected by the antenna selection and installation, discussed in the following sections.

Verify the antenna installation meets all regulations specified in the National Electric Code (NEC) Article 810 with particular attention to clearances from power and lighting conductors, mounting, grounding, and antenna discharge unit.

Antenna Alignment

With line-of-sight microwave communications, optimum system performance requires that the transmitting and receiving antennas are properly aligned. This ensures maximum received signal power at each receiver. Antenna alignment must be achieved in both azimuth (along a horizontal plane) and elevation (along a vertical plane). By ensuring maximum received signal strength, a received signal strength indicator (RSSI) helps the equipment installer determine when alignment is maximized.

TRACER RSSI Test Points

RSSI for the TRACER 64x0 system is provided through the VT100 terminal menus accessed through the RS-232 interface, and it is presented as a series of bars indicating signal strength. More bars means more RSSI, which ensures greater received signal strength and better link performance.

If both the local and remote end of the system are operational, the remote TRACER 64x0 receive power can be viewed from the local TRACER 64x0 VT100 terminal menu interface.

An RSSI test point located on the front panel provides a DC voltage level (relative to the GND test point) that corresponds to the amount of signal being received from the far end’s transmitter. The voltage at this test point can vary from approximately 0 to 5 VDC. An RSSI calibration sheet is shipped with the system to provide the installer a cross-reference between actual received signal level (in dBm) and RSSI voltage. This sheet is useful for verifying link budget calculations and ensuring proper equipment installation.

Real-time Signal Values

The TRACER 64x0 system displays real-time signal values for RX QUALITY, RX POWER, and TX POWER (for both the local and remote units). RX QUALITY values are displayed as a numerical value from 0 to 100, with 0 corresponding to poor signal quality and 100 corresponding to exceptional signal quality.

RX POWER values are displayed in dBm within ±5 dBm accuracy and can vary with extreme temperatures. TX POWER values are displayed in dBm within ±1 dBm accuracy.

Real-time signal values are not supported on all TRACER 64x0 systems. Systems must be ADTRAN calibrated to provide readings for Rx or Tx Power signal levels.

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