Radwin RADWIN 2000 D+, User Manual

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RADWIN 2000 D+ User Manual Release 3.6.00 B ‐ 1
Appendix B: Setting Antenna
Parameters
B.1 Antenna Issues
The choice of Tx Power, antenna gain and cable loss (between the radio and the antenna)
determines the EIRP and is affected by such considerations as radio limitations and regulatory
restrictions.
Before proceeding to antenna installation details, the following background information
should be considered:
B.2 About Single and Dual Antennas
Each RADWIN 2000 D+ ODU is made of two radio transceivers (radios). The radios make use
of algorithms that utilize both Spatial Multiplexing and Diversity resulting in enhanced
capacity, range and link availability. The number of antennas (i.e. radios) used is determined
by user configuration and by automatic system decisions, explained below.
B.2.1 Dual Antennas at the HBS and an HSU
When using dual antennas at both sites (single bipolar antenna or two unipolar antennas) you
can choose between Spatial Multiplexing Mode and Diversity Mode.
Spatial Multiplexing Mode
Under this mode, the system doubles the link capacity. At the same time, it keeps the same
rate and modulation per radio as was used with single antenna, thus increasing capacity,
range and availability.
For example, at 80MHz CBW, using a dual antenna RADWIN 2000 D+ can transmit at
modulation of 256QAM and FEC of 5/6 and get an air rate of 866.7 Mbps, compared to 433.3
Mbps with single antenna.
To work in this mode, each antenna port must be connected to an antenna, the RSS level in
both receivers should be balanced and a minimal separation between the antennas must be