6.2.7.5.3.6 Empty IE

The Empty IE indicates pauses in uplink transmissions. An SS shall not transmit during an Empty IE.

6.2.7.6 Map relevance and synchronization

6.2.7.6.1 Map relevance for framed PHY systems

The information in the DL-MAP pertains to the current frame (i.e., the frame in which it was received). The information carried in the UL-MAP pertains to a time interval starting at the Allocation Start Time measured from the beginning of the frame it was received in and ending after the last allocated minislot. This timing holds for both the TDD and FDD variants of the framed operation. The TDD variant is shown in Figure 39 and Figure 40. The FDD variant is shown in Figure 41 and Figure 42.

Figure 39—Maximum time relevance of PHY and MAC control information (TDD)

Figure 40—Minimum time relevance of PHY and MAC control information (TDD)

Figure 41—Maximum time relevance of PHY and MAC control information (FDD)

> round trip delay + Tproc

Figure 42—Minimum time relevance of PHY and MAC control information (FDD)

6.2.7.6.2 Map relevance for unframed PHY systems

In an unframed PHY system, the DL-MAP contains only an Uplink Time Stamp and does not define what information is being transmitted. All SSs continuously search the downlink signal for any downlink message that is addressed to them. The UL-MAP message in the downlink contains the Time Stamp that indicates the first minislot that the map defines.

The delay from the end of the UL-MAP to the beginning of the first Uplink interval defined by the map shall be greater than maximum round-trip delay plus the processing time required by the SS (see Figure 43).