RF Standard

Radio frequency (3kHz to 300GHz)
ITU-R (United Nations)
- 2.400 to 2.500 GHz (ISM + wireless)
- 5.725 to 5.825 GHz (ISM + wireless)
FCC (US)
- 2.400 to 2.500 GHz (ISM + wireless)
- U-NII-1 (Band 1): 5.15 to 5.25 GHz (Indoor) (wireless)
- U-NII-2 (Band 2): 5.25 to 5.35 GHz (In/outdoor) (DFS:遇radar要讓) (wireless)
- U-NII-2 Extended (Band 3): 5.47 to 5.725 GHz (In/outdoor) (DFS:遇radar要讓) (wireless)
- U-NII-3 (Band 4) 5.725 to 5.825 (In/outdoor) (ISM + wireless)
ETSI (EU)
- 2.400 to 2.500 GHz (ISM + wireless)
- U-NII-1 (Band 1): 5.15 to 5.25 GHz (Indoor) (wireless)
- U-NII-2 (Band 2): 5.25 to 5.35 GHz (Indoor) (DFS:遇radar要讓) (wireless)
- U-NII-2 Extended (Band 3): 5.47 to 5.725 GHz (In/outdoor) (DFS:遇radar要讓) (wireless)

FCC EIRP Limit (Point-to-multipoint links):

FCC EIRP Limit (Point-to-point links):

IEEE 802.11 Channel Layout in 2.4-GHz Band:

IEEE 802.11 Channel Layout in 5-GHz Band:

MIMO Data Rate improvement
- Channel aggregation
- Spatial multiplexing
- MAC layer efficiency
  - Data frame in one burst (只發生一次header)
  - 防止inter-symbol interference, symbol之間, Guard interval 800 nanoseconds
MIMO Reliability
- Transmit beamforming (TxBF) (ClientLink)
  - 調節phase, 去到指定Rx便constructive interference
- Maximal-ratio combining (MRC)
  - 把所有Rx接收到的相同signal再合成一個靚Signal

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