Modulation Coding Schemes, MCS for IEEE 802.11ax

IEEE 802.11ax has a number of defined modualtion coding schemes, ranging from MCS 0 using BPSK for low quality links to MCS 11 using 1024QAM

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In order to optimise the data throughput for all link conditions, IEEE 802.11ax has a series of defined modulation & coding schemes.

These IEEE 802.11ax modulation and coding schemes range from MCS0 using BPSK for the more difficult links, to MCS11 for high quality links which are able to support the highest data throughput.

Between these two extremes there are the other modulation and coding scheme sets that are able to provide different levels of error correction and differnet forms of modulation. There are also different Guard Interval, GI figures that can be used as well.

Table of Modulation Coding Schemes with Associated Data Rates

The table below provides a summary of the various modulation coding schemes available for 802.11ax for the different channel bandwidths and other parameters.

Selecting the right modulation coding scheme is accomplished within the system and depends upon a variety of factors including the wireless communications link quality, the capabilities of the devices and the spectrum available.

IEEE 802.11ax Modulation and coding schemes for single spatial stream
MCS index	Modulation type	Coding rate	Data rate (in Mb/s)
			20 MHz channels		40 MHz channels		80 MHz channels		160 MHz channels
			1600 ns GI	800 ns GI	1600 ns GI	800 ns GI	1600 ns GI	800 ns GI	1600 ns GI	800 ns GI
0	BPSK	1/2	8	8.6	16	17.2	34	36.0	68	72
1	QPSK	1/2	16	17.2	33	34.4	68	72.1	136	144
2	QPSK	3/4	24	25.8	49	51.6	102	108.1	204	216
3	16-QAM	1/2	33	34.4	65	68.8	136	144.1	272	282
4	16-QAM	3/4	49	51.6	98	103.2	204	216.2	408	432
5	64-QAM	2/3	65	68.8	130	137.6	272	288.2	544	576
6	64-QAM	3/4	73	77.4	146	154.9	306	324.4	613	649
7	64-QAM	5/6	81	86.0	163	172.1	340	360.3	681	721
8	256-QAM	3/4	98	103.2	195	206.5	408	432.4	817	865
9	256-QAM	5/6	108	114.7	217	229.4	453	480.4	907	961
10	1024-QAM	3/4	122	129.0	244	258.1	510	540.4	1021	1081
11	1024-QAM	5/6	135	143.4	271	286.8	567	600.5	1134	1201