Airspan AS3010, Hardware Installation Manual

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Hardw are Insta llatio n Guide Radio Site Plannin g
02030311-10 Airspan Networks Inc. 5-5
Prior to performing this test, you need to mount the radio/antenna in the desired
installation spot. In general, you will be looking for frequencies with signal strengths
of –85 dBm or greater.
For using Airspan's spectrum analyzer tool, refer to the WipConfig User's Guide . For
evaluating link quality using the Spectrum Analyzer, see Appendix G, "Evaluating
Link Quality".
5.5. Adjacent Base Station Radios
For installations involving co-location of BSRs, it is important to assign frequencies
of maximum spacing. This is to reduce possible radio interference between
adjacently installed BSRs. In addition, a 1-meter separation must exist between
adjacent BSRs.
5.6. Calculating Link Budget
Link budget is the computation of the maximal achievable reception level for the
communication link between the Base Station and the subscriber site. This level is
the minimum required received signal level (RSS) at the antenna port for the radio to
close the communication link at a given data rate and under the worst-case fading
channel. The weakest signal a receiver can successfully pick up and demodulate at
an acceptable bit-error rate is called receiver sensitivity. This level must be greater
or equal to the radio's receiver sensitivity, which is the minimum RF signal power
level required at the input of a receiver for certain performance (e.g. > BER).
This takes into account the following parameters:
„ Transmit (dBm) EIRP:
Tx transmitter power (dBm) - cable loss (dB) + Tx antenna gain (dBi)
„
Propagation (dB):
Fade Free space loss (dB) = [fade margin] + 32.44 + 20logd(km) +
20logf(MHz), where
f is the frequency in MHz, and d is the distance between
transmitting and receiving radios in km.