• A new Signaling Parameter Channel to convey the FFT size, flat guard interval 31 fraction and slot to interlace mapping.

• An updated specification for the Positioning Pilot Channel.

Revision B of this specification provides an additional option for the Physical layer of the Data Channel referred to as PHY Type 2.The Physical layer option supported by the Revision A of this document is referred to as PHY Type 1. The Signaling Parameter Channel payload definition is updated to include the Physical layer option used by the Data Channel and the status of the Positioning Pilot Channel. The SystemParameters message in the OIS channel has been updated with a new type of MLC records to provide support for MLCs that require higher throughput in a superframe and for MLCs using PHY Type 2 Physical layer option.A new control protocol message is also added to support the higher rate MLCs as well ll as MLCs that use PHY Type 2.

Revision B adds support for the following:

• A new Physical layer option (PHY Type 2) for the Data Channel.

• A new type of MLC record in the OIS channel to signal high rate MLCs and MLCs that employ PHY Type 2 option.

• A new control protocol message for high rate MLCs and MLCs that employ PHY Type 2 option.

• An updated payload for the Signaling Parameters Channel to allow the option for conveying the Physical layer option used by the Data Channel and the presence of Positioning Pilot Channel.