Infinet Wireless: Technical Documentation
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Perform Initial Antenna Alignment

Step 1

Install both units on the pole and direct them at each other (more detailed information about units installation and antenna alignment is described in the section "Units Installing").

Step 2

Turn them on and make sure that the units subsystems are working properly. This can be done by LED indication.

Center

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Center
Scroll Title
titleTable - Indicator Panel Description
LEDNormal stateFunction
Power

On

On - power is applied to the device

Off - no power is applied or improper power source

SYNCOnTDD-synchronization
SFPOnEthernet link
GE1OnEthernet link
GE0OnEthernet link
RFOnRF link. Blinking while establishing RF link
Step 3

Perform coarse alignment using built-in signal strength indicators.

Note
titleNOTE

 The more indicators are on, the better wireless connection is established. The blinking indicator means an intermediate state. The more often the indicator blinks the higher level connection is established.

Step 4

Perform fine alignment using the "Alignment tool" available in the Web interface or "xginfo stat" output in the CLI. Try to  maximize CINR and RSSI readings. Please follow the detailed indications from section Antenna alignment for a proper antenna alignment.

Note
titleNOTE

 If “Absolute RSSI” value goes above -40 dBm, decrease "Tx power" at the opposite side in order to keep it within -40...-50 dBm for the best performance.

Step 4 - Optimize the link performance

  • Adjust maximal link distance parameter based on the measured distance.

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titleNOTE

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Optimize the link performance

Method 1
Depending on the values for CINR, RSSI change the following parameters:
  • Decrease/increase the Tx power level in order to have the CINR above 28 dB and the RSSI between -40…-60 dBm.
  • Enable ATPC mode with setting "Target RSSI" value. The RSSI value of the master tries to engage the target range, the center value of which is the "Target RSSI".
Method 2

Use the Spectrum Analyzer tool built-in the Web GUI in order to determine the best frequency and to check the radiation levels in the installation area. Frequency should be left to "auto" in case of Instant DFS units (for unlicensed bands), or it should be set to a specific value (in countries where DFS is not mandatory) on the master unit after performing the Spectrum Analyzing test on both units.

Method 3

Select the most appropriate air frame period:

  • A shorter frame period gives lower latency, but also has higher overheads.
  • Using longer frame periods cuts down overheads, but increases the latency.
Method 4
Enable "Short Cyclic Prefix" mode in order to mitigate inter-symbol interference due to multipath propagation environment.
Method 5
Enable "Control Block Boost" mode that improves link availability in the most difficult propagation and interference conditions due to the radio frame with control information transfer at duplicate transmit power.
Method 6
Enable "Instant DFS" that gives availability to change frequency without link interruption.
Method 7

Monitor air block error rate by checking the "Acc TBER"  parameter in the "Status" page or in "xginfo stat" output and adjust

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the AMC strategy if necessary.

Note
titleNOTE

 Acceptable error rate depends on the application. See some examples in the table below.

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Center
Scroll Title
titleTable - Acceptable error rates for different applications
ApplicationAcceptable error rate
TCP-based applications (web, FTP, etc.)10-4
Voice-over-IP10-5
UDP video (CCTV, IPTV, etc)10-6
TDM-over-IP10-7...10-9

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The "AMC Stratefy" may be changed depending on customer erquirements:

  • “conservative” assumes using higher CINR thresholds in order to minimize the error rate.
  • “aggressive” lowers the thresholds in order to use higher modulation levels and thus increase the throughput.
  • “normal” represents a balance between the error rate and throughput values.

It is recommended to use “normal” strategy initially and adjust it based on target and actual TBER values

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