802.11aj PHYs

What frequency bands does 802.11aj PHY support?

802.11aj PHY operates in the 45 GHz and 59–64 GHz mmWave frequency bands.

What channel bandwidths are defined for 802.11aj PHY?

It supports 2.16 GHz wide channels similar to 802.11ad.

Does 802.11aj PHY use OFDM or SC modulation?

802.11aj PHY uses single carrier (SC) and OFDM modulations adapted for mmWave frequencies.

What modulation schemes are supported in 802.11aj PHY?

Supports BPSK, QPSK, 16-QAM, 64-QAM, and 256-QAM.

How does 802.11aj PHY achieve high data rates?

Through wide bandwidth channels (2.16 GHz) and high-order modulation schemes up to 256-QAM.

What is the symbol duration in 802.11aj PHY?

The symbol duration is typically 4.0 or 3.6 microseconds depending on the modulation.

Does 802.11aj PHY support MIMO?

No, 802.11aj does not include MIMO; it relies on directional beamforming.

How does 802.11aj PHY handle beamforming?

PHY layer supports training sequences for beamforming but beamforming is coordinated at MAC.

What is the typical PHY data rate range in 802.11aj?

Data rates can range from tens of Mbps up to several Gbps depending on conditions and MCS.

Are there different PHY modes in 802.11aj?

Yes, it defines SC PHY and OFDM PHY modes optimized for mmWave transmission.

How is PHY synchronization achieved in 802.11aj?

Using preamble sequences designed for timing and frequency synchronization.

Does 802.11aj PHY modify the PPDU format?

Yes, it includes adaptations for channel bandwidth and beamforming support.

How does 802.11aj PHY handle interference and noise?

Directional antennas reduce interference; PHY uses adaptive coding and modulation.

What coding rates are supported in 802.11aj PHY?

Common code rates include 1/2, 2/3, 3/4, and 5/6.

Is 802.11aj PHY backward compatible with 802.11ad?

Yes, it maintains backward compatibility for interoperability.

What is the role of the scrambler in 802.11aj PHY?

It randomizes data patterns to improve signal integrity and reduce interference.

Does 802.11aj PHY support power saving at PHY layer?

PHY works in conjunction with MAC for power save but includes low-power states.

What types of channel coding are used in 802.11aj PHY?

Uses convolutional coding and optional LDPC coding for error correction.

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