Cambium Networks cnWave, Руководство пользователя

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System Planning 79
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Perform traffic test on one link at a time and then simultaneously.
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If the simultaneous traffic results show degradation along with transmit power that is railed
high to maximum, consider the following tasks:
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Setting the two sectors on different channels or
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Capping the maximum power of the short range link.
Figure 53 illustrates the problem and the solution for near-far radio.
Figure 53: Near-far radio - Problem and solution
Early weak interference
Early weak interference occurs when the receiver correlates to a preamble from an unwanted node, with
the same Golay code (as desired). If the receiver starts decoding the preamble from the wrong node, it
may be too late to recover the preamble from the correct node for that cycle.
Terragraph has four Golay codes to mitigate this interference. Users can select the Golay codes {1,2,3}.
Note
Golay 0 is used for another purpose. Therefore, avoid selecting the Golay 0 (The use of
Golay 0 has been deprecated in System Release 1.2).
Consider the following points specific to the Golay codes in 802.11ad/ay:
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The 802.11ad/ay frame consists of PHY preamble, which consists of short training frame (STF) and
Channel Estimation Symbol (CES).
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The STF and CES are made up of complimentary Golay codes. Due to the repetition of the Golay
codes, the signal can be correlated with even low SNRs.
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This PHY preamble is used for frequency synchronization, timing synchronization, and channel
estimation.