Method and apparatus for reordering fragments within a MAC layer service data unit within a downlink frame

A communication device comprising:

• receiver circuitry receiving signals from a source external to the communication device;
• a physical layer processor coupled to the receiver and processing the signals in accordance with a predetermined physical layer coding scheme to recover a downlinik frame, the physical layer generating a plurality of protocol data units (PDUs) comprising a plurality of fragments of the downlinik frame and an end-of-frame signal, each of the plurality of fragments including fragmentation control information and fragment number information;
• and
• a Medium Access Control (MAC) layer processor coupled to the physical layer processor and receiving the plurality of PDUs therefrom including the plurality of fragments, the MAC layer processor pre-processing the plurality of fragments of the downlink frame to reassemble MAC layer Service Data Units (MSDUs) therefrom by reordering the plurality of fragments into one or more reassembled MSDUs in response to the fragmentation control information and the fragment number information of each of the plurality of fragments, the fragmentation control information indicating at least a first fragment of one of the one or more MSDUs, the MAC layer processor further, in response to detecting the end-of-frame signal indicating that all of the plurality of fragments for a downlink frame have been received, post-processing the plurality of fragments of the downlink frame by determining whether each of the one or more reassembled MSDUs is a complete MSDU and delivering any complete MSDUs to a next layer or by determining whether each of the one or more reassembled MSDUs is an incomplete MSDU and then determining if the incomplete MSDU is a last not yet complete MSDU with no missing fragments in response to the last not yet complete MSDU having no fragments missing between a fragment thereof having a lowest value fragment number information and a fragment thereof having a highest value fragment information, and saving the incomplete MSDU if the incomplete MSDU is a last not yet complete MSDU with no missing fragments or discarding the incomplete MSDU if it is not a last not yet complete MSDU or if it is a last not yet complete MSDU that has missing fragments.

A method for generating downlink frames comprising the steps of:

• splitting a Medium Access Control (MAC) layer Service Data Units (MSDUs) into one or more data units;
• generating fragments from the one or more data units, each of the fragments including fragmentation control information, fragment number information and one of the one or more data units;
• and
• assigning a number of the fragments to one of the downlink frames, the number being less than or equal to a predetermined number of possible fragments, wherein the predetermined number of possible fragments is one-half of a total number of possible fragments, the total number of possible fragments being 211.