Methods and procedures for high speed UE access
A terminal random access procedure is improved by allowing a mobile terminal to correctly map signature indexes onto cyclic shifted Zadoff-Chu (ZC) sequences when the deployed cells support a high-speed mobility by informing a mobile terminal whether a cell supports high-speed mobility.
1. A method of establishing a communication link between a mobile terminal and a network, the method comprising:
receiving, by the mobile terminal, a high-speed related parameter from the network, the high-speed related parameter representing either ‘TRUE’ or ‘FALSE’, wherein TRUE corresponds to a restricted set of cyclic shifts and FALSE corresponds to an unrestricted set of cyclic shifts;
if the high-speed related parameter represents TRUE,
generating, by the mobile terminal, a first plurality of sequences for random access from Zadoff-Chu (ZC) sequences with zero correlation zones using the restricted set of cyclic shifts; and
transmitting, by the mobile terminal, one of the generated first plurality of sequence to the network for the random access, and
if the high-speed related parameter represents FALSE,
generating, by the mobile terminal, a second plurality of sequences for random access from Zadoff-Chu (ZC) sequences with zero correlation zones using the unrestricted set of cyclic shifts; and
transmitting, by the mobile terminal, one of the generated second plurality of sequences to the network for the random access.
2. The method of claim 1 , wherein the high-speed related parameter comprises one bit.
3. A method of establishing a communication link between a mobile terminal and a network, the method comprising:
transmitting, by the network, a high-speed related parameter to the mobile terminal, the high-speed related parameter representing either ‘TRUE’ or ‘FALSE’, wherein TRUE corresponds to a restricted set of cyclic shifts and FALSE corresponds to an unrestricted set of cyclic shifts; and
if the high-speed related parameter represents TRUE,
receiving, by the network from the mobile terminal, one of a first plurality of sequences for random access from Zadoff-Chu (ZC) sequences with zero correlation zones that are generated using the restricted set of cyclic shifts, and
if the high-speed related parameter represents FALSE,
receiving, by the network from the mobile terminal, one of a second plurality of sequences for random access from Zadoff-Chu (ZC) sequences with zero correlation zones that are generated using the unrestricted set of cyclic shifts.
4. The method of claim 3 , wherein the high-speed related parameter comprises one bit.
5. A mobile terminal for establishing a communication link with a network, the mobile terminal comprising:
a transmitting/receiving unit configured to transmit and receive messages between the mobile terminal and the network;
a display unit configured to display user interface information;
an input unit configured to receive inputs from a user; and
a processing unit configured to:
receive a high-speed related parameter from the network, the high-speed related parameter representing either ‘TRUE’ or ‘FALSE’, wherein TRUE corresponds to a restricted set of cyclic shifts and FALSE corresponds to an unrestricted set of cyclic shifts;
if the high-speed related parameter represents TRUE,
generate a first plurality of sequences for random access from Zadoff-Chu (ZC) sequences with zero correlation zones using the restricted set of cyclic shifts; and
transmit one of the generated first plurality of sequences to the network for the random access, and
if the high-speed related parameter represents FALSE,
generate a second plurality of sequences for random access from Zadoff-Chu (ZC) sequences with zero correlation zones using the unrestricted set of cyclic shifts; and
transmit one of the generated second plurality of sequences to the network for the random access.
6. The mobile terminal of claim 5 , wherein the high-speed related parameter comprises one bit.
7. A network for establishing a communication link with a mobile terminal, the network comprising:
a transmitter configured to transmit messages to the mobile terminal;
a receiver configured to receive messages from the mobile terminal; and
a controller configured to:
transmit, to the mobile terminal, a high-speed related parameter representing either ‘TRUE’ or ‘FALSE’, wherein TRUE corresponds to a restricted set of cyclic shifts and FALSE corresponds to an unrestricted set of cyclic shifts; and
if the high-speed related parameter represents TRUE,
receive, from the mobile terminal, one of a first plurality of sequences for random access from Zadoff-Chu (ZC) sequences with zero correlation zones that are generated using the restricted set of cyclic shifts, and
if the high-speed related parameter represents FALSE,
receive, from the mobile terminal, one of a second plurality of sequences for random access from Zadoff-Chu (ZC) sequences with zero correlation zones that are generated using the unrestricted set of cyclic shifts.
8. The network of claim 7 , wherein the high-speed related parameter comprises one bit.