FIG. 7 is a schematic diagram illustrating subframe 700. The subframe 700 may include two slots, each having a length of about 0.5 milliseconds, and including seven symbols. According to one embodiment, the second half of the last symbol 720 may be punctured. Therefore, the receiving UE may obtain at least 33.33 microseconds of guard interval as the Tx/Rx switching time.

In other embodiments, the guard time to accommodate the Tx/Rx switching time may be achieved by partial, full, or no puncturing of the last symbol according to a particular D2D application. As an example, the last symbol may not need to be punctured at all if guard time handling is not handled within the D2D discovery or communication region. Instead, the provision for Tx/Rx switching time may be handled via scheduler restrictions for D2D and WAN subframe boundaries.

Compared to the subframe 500 or 600, the subframe 700 may provide better coding gain that improves packet detection probability. In various embodiments, the first half of the first symbol 710 is not punctured. Instead, the first half of the first symbol 710 may be used to generate an effective CP 730 for the second half 740 at the first symbol 710. Consequently, the CP 730 may provide at least 33.33 microseconds, in addition to the normal or extended CP applied for D2D subframes, for the receiving UE to set up AGC. As an example, the CP 730 may employ a CP length of 38.03 microseconds (e.g., 33.33 μs of the first half of the first symbol, plus 4.7 μs of the normal CP provided for the first symbol) to accommodate the AGC setting time. Compared to the subframe 500 or 600, the subframe 700 does not provide any additional protection to the second symbol, but provides better coding gain.