Kwikbit K60x, Руководство пользователя

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K60x User Guide
10 K60x User Guide
2.3 System Throughput
The K60x system is based on the IEEE 802.11ad standard. It uses time division duplexing
(TDD) access mode, employing a single frequency for both transmit and receive paths. The
throughput for the downlink and uplink depends on a downlink-to-uplink frame bandwidth
ratio. The ratio is automatically adjusted based on the offered load in each direction, taking
into account all remotes connected to a hub in PtMP.
The system’s throughp ut depends on the Modulation and Coding Rate (MCS) which varies
according to link and signal conditions. The following table details Ethernet uplink and
downlink combined throughput for a K60x link.
Throughput Performance for Cyclic Prefix of 1/8
MCS
Index
Modulation NCBPS Repetitions Code Rate
Data Rate
(Mbit/s)
1 π/2 BPSK 1 2 1/2 310
2 π/2 BPSK 1 1 1/2 620
3 π/2 BPSK 1 1 5/8 775
4 π/2 BPSK 1 1 3/4 930
5 π/2 BPSK 1 1 13/16 1007
6 π/2 QPSK 2 1 1/2 1240
7 π/2 QPSK 2 1 5/8 1550
8 π/2 QPSK 2 1 3/4 1860
The system will run at MCS Index 8 under good conditions and within the units’ specified
ranges. Co-channel interference, obstructions to the line of sight, and attenuative weather
such as rain, snow, and fog will cause the MCS Index to drop. This adaptive feature enables
the system units to maintain communications at a slower data rate in adverse conditions.
At higher elevations, the 60 GHz frequency provides some enhanced performance due to
lower oxygen density.