Random access channel response handling with aggregated component carriers
View Patent ↗Disclosed herein are methods, computer program instructions and apparatus for performing random access procedures in a wireless communication system. A method includes receiving at a network access node, in different time and frequency resources that are allocated for preamble transmission, and in different ones of a plurality of component carriers, a plurality of random access requests from individual ones of a plurality of user equipments; and transmitting a corresponding plurality of random access responses in a time and frequency resource of a single component carrier.
1. A method, comprising:
receiving at a network access node, in different time and frequency resources that are allocated for preamble transmission, and in different ones of a plurality of component carriers, a plurality of random access requests from individual ones of a plurality of user equipments; and
transmitting a corresponding plurality of random access responses in a time and frequency resource of a single component carrier.
2. The method of claim 1 , where the plurality of random access responses are transmitted on a physical downlink shared channel.
3. The method as in claim 1 , where the single component carrier is selected freely by the network access node from a set of component carriers.
4. The method as in claim 1 , where the single component carrier is selected by the network access node in accordance with at least one rule.
5. The method of claim 4 , where the at least one rule comprises selecting the single component carrier as being one having a first available downlink slot and, for a case where more than one of the component carriers each simultaneously contain an available downlink slot, selecting as the single component carrier the component carrier having the highest frequency subcarrier.
6. The method as in claim 1 , where the single component carrier is specified by the use of explicit signaling.
7. The method as in claim 6 , where the explicit signaling comprises use of system information transmitted from the network access node.
8. The method as in claim 1 , where the corresponding plurality of random access responses are for a first type of user equipment and for a second type of user equipment, and where there is at least one random access response for one of the second type of user equipment that is placed in a message at a location that need not be read by the first type of user equipment.
9. The method as in claim 8 , where the message comprises an indicator that is set for indicating that the message contains the at least one random access response for one of the second type of user equipment.
10. The method as in claim 9 , where the location that need not be read by the first type of user equipment is in a message padding portion of the first type of user equipment.
11. The method as in claim 10 , where the indicator is placed in a message padding portion, or is placed in one or more bits of the message that are considered by the first type of user equipment as being reserved.
12. The method as in claim 1 , that is performed as a result of the execution of program instructions stored in a computer readable medium.
13. An apparatus, comprising:
a controller configured to operate with a wireless receiver and a wireless transmitter, said controller further configured to respond to a reception in different time and frequency resources that are allocated for preamble transmission, and in different ones of a plurality of component carriers, a plurality of random access requests from individual ones of a plurality of user equipments and to transmit a corresponding plurality of random access responses in a time and frequency resource of a single component carrier.
14. The apparatus of claim 13 , where the plurality of random access responses are transmitted on a physical downlink shared channel.
15. The apparatus as in claim 13 , where the single component carrier is selected freely by the controller from a set of component carriers.
16. The apparatus as in claim 13 , where the single component carrier is selected by the controller in accordance with at least one rule, where the at least one rule causes the controller to select the single component carrier as being one having a first available downlink slot and, for a case where more than one of the component carriers each simultaneously contain an available downlink slot, to select as the single component carrier the component carrier having the highest frequency subcarrier.
17. The apparatus as in claim 13 , where the single component carrier is specified by the use of explicit signaling.
18. The apparatus as in claim 17 , where the explicit signaling comprises use of system information.
19. The apparatus as in claim 13 , where the corresponding plurality of random access responses are for a first type of user equipment and for a second type of user equipment, and where there is at least one random access response for one of the second type of user equipment that is placed in a message padding portion that need not be read by the first type of user equipment.