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802.11ad802.11ad is a specially designed to work in extremely high frequency and with extremly wide bandwidth offering the high throughput relatively simple structure. What I mean by 'relatively simple structure' mean 'without using high degree of MIMO and high order modulation technique'. It doesn't really mean that 802.11ad is easy to implement. In terms implementation, we need to overcome various technical issues that should work at mmWave (60 Ghz) range. Overall characteristics (features) of 802.11ad can be summarized as in the following diagram. In terms of throughput, you may see 802.11ad does not provide much higher throughput than 802.ac. Actually theoretical max throughput of 802.11ac (8 stream, 256 QAM) is higher than 802.11ad. However, in regular / common operation, higher throughput would be more easily achieved with 802.11ad. At least as of now (Jun 2017), 802.11ad does not support MIMO and does not support very high order modulation scheme (e.g, 64 QAM or higher). Then you may ask.. how can we achieve such a high throughput without using higher order modulation or high degree MIMO ? The answer is simple.. just use super-wide bandwidth :). A single channel 802.11ad bandwidth is up to 1.88 Ghz (almost 2 Ghz). This can be a big challenge in baseband implementation. (Of course, RF side challenge is to develop / implement 60 Ghz components. PHY Frame
Control PHY Frame
Single Carrier PHY Frame
Low Power Single Carrier PHY Frame
OFDM PHY Frame
Additional MAC Frame TypesIn 802.11ad, Following new Frame Types are added to the existing type.
When Frame Extension type is configured, the structure of Frame Control field is defined as follows The Control Frame Extension bit field is defined as follows (802.11ad - Table 8-1aControl Frame Extension).
References :[1] Wikipeida : Wireless Gigabit Alliance [2] Understanding IEEE 802.11ad Physical Layer and Measurement Challenges [4] WLAN 802.11ad physical layer
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