Kwikbit Inc. PTP55DP Manuale Utente
M4-2000
User Guide
Kwikbit M4-2000 User Guide
Confidential & Proprietary
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However, each radio can split the channel into separate downlink and uplink frequencies. This
hybrid mode maintains the TDD channel turn-around alternating between uplink and downlink, but
also alternates the transmit frequency between uplink and downlink.
Each of the dual radios is capable of hybrid TDD operation, with independently configured
Transmit and Receive frequencies for each radio.
Bearer plane data is always distributed evenly between the two radios.
also alternates the transmit frequency between uplink and downlink.
Each of the dual radios is capable of hybrid TDD operation, with independently configured
Transmit and Receive frequencies for each radio.
Bearer plane data is always distributed evenly between the two radios.
4.6.2 MIMO / XPIC operation
Each radio in the M4-2000 system operates in Cross Polarization Interference Canceling (XPIC)
mode with dual data streams doubling the channel capacity.
4.6.3 Adaptive modulation and coding
Each M4-2000 unit adapts its modulation and coding level to maximize data throughput based on
received signal quality.
Each receiver evaluates signal quality by measuring signal strength, signal to noise ratio, and the
rate of corrected bit errors. The receiver feeds this information back over the air to its peer
received signal quality.
Each receiver evaluates signal quality by measuring signal strength, signal to noise ratio, and the
rate of corrected bit errors. The receiver feeds this information back over the air to its peer
transmitter to optimize the modulation level used. The MCS level is continually adjusted on 1ms
frame boundaries.
The system automatically switches between nine modulation and coding modes, indicated by
frame boundaries.
The system automatically switches between nine modulation and coding modes, indicated by
number as shown
Level
Modulation /
Coding scheme
0
QPSK 1/4
1
QPSK 1/2
2
QPSK 3/4
3
16QAM 1/2
4
16QAM 3/4
5
64QAM 4/6
6
64QAM 5/6
7
256QAM 6/8
8
256QAM 7/8
The most robust is MCS level 1, while the highest performance is level 8. The following tables
illustrate maximum achievable data rates for a 5GHz M4-2000 system with different packet sizes
and modulation and coding levels. These values include the additional throughput gained via
header compression (see section 4.6.4).
header compression (see section 4.6.4).