Wi-Fi Integration to the 4G Mobile Network

4802.11n Interface

4.1. MAC layer evolution

Table 4.1 summarizes the features provided by the MAC (Medium Access Control) layer.

Table 4.1. Features of MAC layer

Features	Mandatory/optional	Description
Reception A-MPDU	Mandatory	MAC frame aggregation
Transmission A-MPDU	Optional
Reception A-MSDU	Mandatory	Aggregation of MAC frame payload
Transmission A-MSDU	Optional
Block Ack	Mandatory	Acknowledgment for a block of MAC frames
Protection	Mandatory	Detection of radio channel occupancy time by non-802.11n compatible stations
RIFS	Mandatory	Reduced inter-frame interval
Spatial Multiplexing Power Save	Mandatory	Power save by reducing the number of spatial flows
Power Save Multi-Poll	Optional	Power save by modifying the radio access procedure for smaller frames
Non–TKIP	Mandatory	TKIP is no longer allowed
Phased Coexistence Operation	Optional	Alternating radio channels at 20 and 40 MHz

4.1.1. Management frames

4.1.1.1. HT Capabilities information element

The management frames indicate that the access point has an 802.11n interface by including the HT (High Throughput) Capabilities information element.

The information provided by the HT Capabilities Info field is described in Table 4.2.

Table 4.2. Information of HT Capabilities Info field

Information	Designation
LDPC Coding Capability	LDPC error correction code
Supported Channel Width Set	Bandwidth of the radio channel (20 MHz / 40 MHz)
SM Power Save	Power save for spatial multiplexing