OpenAirInterface Physical Layer (PHY) Specifications
[OpenAirInterface Layer1/2 Specifications]

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Detailed Description

This clause specifies the PHY layer for a multiple-antenna orthogonal frequency-division multiple-access (OFDMA) system applied and the generic openair MAC interface.

openair PHY

The specification is intended for reconfigurable equipment, so that actual parameters and mechanisms can be configured prior to deployment of the equipment or potentially over-the-air, although the latter is not yet supported by any of the openair MAC implementations. The PHY and MAC layers are tightly coupled so that the MAC entity can directly influence the occupied physical resources. The OFDMA system provides the means for transmitting several multiple-bitrate streams (multiplexed over sub-carriers and antennas) in parallel. Moreover, PHY signaling strategies are included to provide the means for exploiting channel state feedback at the transmitters in order to allow for advanced PHY allocation of OFDMA resources via the MAC. Modulation and channel coding formats are generic allowing for specific techniques to be employed in different deployment scenarios although configurations based on the 802.11a legacy standard (binary/quaternary phase shift keying BPSK/QPSK, 16-point quadrature amplitude modulation (16-QAM), 64-QAM, rate 1/2,2/3,3/4 punctured convolutional codes) are provided here. The specifications are not specific to any frequency band or bandwidth, although the minimum expected channel bandwidth should not be less than 1 MHz.

Modules
	Scope
	This subclause describes the PHY services provided to the openair MAC.
	Framing and Channel Multiplexing
	Coded Modulation and H-ARQ
	OpenAirMesh makes use of punctured binary codes (64-state rate 1/2 convolutional or 8-state rate 1/3 3GPP/LTE Turbo code).

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