System and method for contention-free random access

A user equipment (UE) comprising:

• a processor;
• and
• a non-transitory computer readable storage medium storing programming for execution by the processor, the programming including instructions to:
• receive, from a communications controller, symbols of a first subframe comprising a first downlink control information (DCI), wherein the first DCI corresponds to a physical downlink control channel (PDCCH) order,
• search for the first DCI in a first downlink control channel in common search space of the first subframe and a second downlink control channel in a UE specific search space of an enhanced physical downlink control channel (ePDCCH) in a data region of the first subframe,
• obtain random access parameters from the first DCI, wherein the first DCI is in the data region of the first subframe,
• transmit, to the communications controller, a random access preamble in accordance with the random access parameters, and
• receive a second DCI in a control region of a second subframe, wherein the second DCI comprises scheduling information for a random access response.

A method for initiating random access, the method comprising:

• generating a downlink control information (DCI) comprising random access parameters;
• selecting a first control channel from a set including a physical downlink control channel (PDCCH) of a first subframe and an enhanced physical downlink control channel (ePDCCH) of the first subframe;
• mapping the DCI to the first control channel;
• and
• transmitting, by a communications controller to a user equipment (UE), symbols of the first subframe comprising the DCI in the first control channel, wherein the DCI corresponds to a PDCCH order, and wherein the DCI is in a data region of the first subframe.

A communications controller comprising:

• a processor;
• and
• a non-transitory computer readable storage medium storing programming for execution by the processor, the programming including instructions to:
• generate a downlink control information (DCI) comprising random access parameters,
• select a control channel from a set including a physical downlink control channel (PDCCH) of a subframe and an enhanced physical downlink control channel (ePDCCH) of the subframe,
• map the DCI to the control channel, and
• transmit, to a user equipment (UE), symbols of the subframe comprising the DCI in the control channel, wherein the DCI corresponds to a PDCCH order, and wherein the DCI is in a data region of the subframe.

A method for initiating random access, the method comprising:

• generating a downlink control information (DCI) comprising random access parameters;
• selecting a first control channel from an enhanced physical downlink control channel (ePDCCH) of a subframe;
• mapping the DCI to the first control channel;
• and
• transmitting, by a communications controller to a user equipment (UE), symbols of the subframe comprising the DCI in the first control channel, wherein the DCI corresponds to a PDCCH order, and wherein the DCI is in a data region of the subframe.

A communications controller comprising:

• a processor;
• and
• a non-transitory computer readable storage medium storing programming for execution by the processor, the programming including instructions to:
• generate a downlink control information (DCI) comprising random access parameters,
• select a control channel from an enhanced physical downlink control channel (ePDCCH) of a subframe,
• map the DCI to the control channel, and
• transmit, to a user equipment (UE), symbols of the subframe comprising the DCI in the control channel, wherein the DCI corresponds to a PDCCH order, and wherein the DCI is in a data region of the subframe.