Radwin 2000+ SERIES, User Manual

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RADWIN 2000+ Series User Manual Release 4.2.40 C ‐ 2
Single Antennas at Both Sites
Upon selecting Antenna Type as Dual, a RADWIN 2000+ Series radio automatically selects this
mode and doubles the air rates.
The RADWIN Manager indicates a case of unbalanced RSS between the two antennas in the
center panel.
Diversity Mode
Diversity Mode uses two antennas to improve the quality and reliability of the link. Often,
there is not a clear line ‐ of ‐ sight (LOS) between transmitter and receiver. Instead the signal is
reflected along multiple paths before finally being received.
Each such “bounce” can introduce phase shifts, time delays, attenuations, and even
distortions that can destructively interfere with one another at the aperture of the receiving
antenna. Antenna diversity is especially effective at mitigating these multi ‐ path situations.
This is because multiple antennas afford a receiver several recordings of the same signal. Each
antenna will be exposed to a different interference environment. Thus, if one antenna is
undergoing a deep fade, it is likely that another has a sufficient signal. Collectively such a
system can provide a robust link.
Antenna diversity requires a separation between the antennas; this is done by using a dual ‐
polarization antenna or by two spatially separated antennas.
Use Diversity instead of Spatial Multiplexing in the following situations:
• When the system cannot operate in Spatial Multiplexing Mode
• When one of the receivers has high interference compared to the second receiver (i.e.
the system is “unbalanced”)
• When you achieve higher capacity in Diversity Mode than in Spatial Multiplexing Mode
• When high robustness is of importance and the capacity of Diversity Mode is sufficient
(up to 25 Mbps full duplex)
C.2.2 Single Antennas at Both Sites
By selecting a single antenna at both sites, the radio units operate with a single radio that is
connected to the ANT 1 connector. The second radio is automatically shut down.
C.2.3 Single at One Site, Dual Antennas at the Other
In this mode one of the sites uses the radio unit with a single antenna while the other site
uses the radio unit with a dual antenna.
The advantages in this mode in comparison to using a single antenna in both sites are
doubled total Tx Power and additional polarization and/or space diversity (depending on the
polarization of installed antennas).
The air rates used in this mode are same as when using single antennas in both sites.