TECHNIQUE FOR PERFORMING A RANDOM ACCESS PROCEDURE OVER A RADIO INTERFACE

• US 20130308615A1
• Filed: 07/25/2013
• Published: 11/21/2013
• Est. Priority Date: 10/21/2005
• Status: Active Grant

• Current Assignee: Telefonaktiebolaget LM Ericsson
• Original Assignee: Telefonaktiebolaget LM Ericsson
• Inventors: BALDEMAIR, Robert, DAHLMAN, Erik, HAARTSEN, Jacobus Cornelis, PARKVALL, Stefan, EDVARDSSON, Maria
• Granted Patent: US 10,219,302 B2
• Time in Patent Office: Days
• US Class Current: 370/336
• CPC Class Codes: H04B 7/2681 Synchronisation of a mobile station with one base station
• CPC Class Codes: H04J 3/0605 Special codes used as synchronising signal
• CPC Class Codes: H04W 56/001 Synchronization between nodes
• CPC Class Codes: H04W 56/0045 compensating for timing error by altering transmission time
• CPC Class Codes: H04W 72/1268 of uplink data flows
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access
• CPC Class Codes: H04W 74/0891 for synchronized access

Abstract

The invention relates to a technique for performing a random access procedure over a radio interface, for example between a mobile terminal and a radio base station of a mobile network. A method aspect of the invention comprises the steps of transmitting a synchronization request for synchronization information; receiving synchronization information in response to the synchronization request; and transmitting, based on at least one transmission parameter adjusted in accordance with the synchronization information, a resource request for data transmission resources.

Claims

1. A method of performing a random access procedure over a radio interface, the method comprising the following in a mobile terminal:

transmitting a synchronization request for synchronization information;

receiving synchronization information in response to the synchronization request;

transmitting, based on at least one transmission parameter adjusted in accordance with the synchronization information, a resource request for data transmission resources; and

using a timer mechanism providing an indication related to the validity of the at least one transmission parameter used by the mobile terminal to keep the mobile terminal in synchronization.

2. The method according to claim 1,

further comprising:

receiving resource information in response to the resource request; and

transmitting data using resources in accordance with the resource information.

3. The method according to claim 2,

further comprising transmitting, in case further data is to be transmitted, at least the further resource request.

4. The method according to claim 1,

further comprising starting a synchronization timer in response to at least one of the reception of synchronization information and the transmission of data.

5. The method according to claim 4,

wherein the synchronization timer is set according to a predicted validity of the synchronization information.

6. The method according to claim 4,

wherein the synchronization timer is set according to a measured velocity of the mobile terminal.

7. The method according to claim 4,

wherein a further synchronization request is transmitted on expiry of the synchronization timer.

8. The method according to claim 1,

further comprising transmitting at least one ping signal (716) for maintaining synchronization.

9. The method according to claim 8,

wherein the ping signal comprises signalling data.

10. The method according to claim 8,

wherein the ping signal is transmitted on expiry of the synchronization timer.

11. The method according claim 8,

wherein the ping signal is transmitted in response to a polling request received over the radio interface.

17. A computer program product comprising program code portions for performing the acts of claim 1 when the computer program product is executed on one or more computing devices.

18. The computer program product of claim 17, stored on a computer readable recording medium.

12. A method of performing a random access procedure over a radio interface, the method in a radio base station comprising:

receiving a synchronization request for synchronization information;

transmitting, based on the synchronization request, the synchronization information;

receiving, based on at least one transmission parameter adjusted according to the synchronization information, a resource request for data transmission resources; and

using a timer mechanism providing an indication related to the validity of the at least one transmission parameter used by the mobile terminal to keep the mobile terminal in synchronization.

13. The method according to claim 12,

further comprising:

transmitting resource information in response to the resource request; and

scheduling resources according to the resource information.

14. The method according to claim 12,

further comprising receiving at least one further resource request.

15. The method according to claim 12,

further comprising starting a synchronization timer in response to at least one of the reception of the synchronization request, the reception of the resource request and the reception of data.

16. The method according to claim 15,

further comprising transmitting, on expiry of the synchronization timer, a request for a ping signal.

19. A mobile terminal adapted for performing a random access procedure over a radio interface, the mobile terminal comprising:

a sync-request component adapted for transmitting a synchronization request for synchronization information;

a sync-response component adapted for receiving synchronization information in response to the synchronization request;

a transmission control component adapted for transmitting, based on at least one transmission parameter adjusted according to the synchronization information, a resource request for data transmission resources; and

a timer component adapted to provide an indication related to the validity of the at least one transmission parameter used by the mobile terminal to keep the mobile terminal in synchronization.

20. A radio base station adapted for performing a random access procedure over a radio interface, the base station comprising:

a sync-request component adapted for receiving a synchronization request for synchronization information;

a sync-response component adapted for transmitting, based on the synchronization request, the synchronization information;

a resource scheduling component adapted for receiving, based on at least one transmission parameter adjusted according to the synchronization information, a resource request for data transmission resources; and

a timer component adapted to provide an indication related to the validity of the at least one transmission parameter used by the mobile terminal to keep the mobile terminal in synchronization.