RESOURCE REQUESTS IN SMALL CELL NETWORKS

• US 20150016350A1
• Filed: 06/13/2014
• Published: 01/15/2015
• Est. Priority Date: 07/09/2013
• Status: Abandoned Application

• Current Assignee: Fujitsu Limited
• Original Assignee: Fujitsu Limited
• Inventors: MOULSLEY, Timothy, BUCKNELL, Paul
• Application Number:
  US14/303,879
• Publication Number:
  US 20150016350A1
• Time in Patent Office: Days
• US Class Current: 370/329
• CPC Class Codes: H04W 48/20 Selecting an access point
• CPC Class Codes: H04W 72/02 Selection of wireless resources by user or terminal
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/21 in the uplink direction of a wireless link, i.e. towards the network
• CPC Class Codes: H04W 74/004 in the uplink, i.e. towards network
• CPC Class Codes: H04W 84/045 using private Base Stations, e.g. femto Base Stations, home Node B

Abstract

A Small Cell Network in which a terminal (1) is simultaneously served by a macro cell (10) and one or more small cells (20, 22, 24). When suitable uplink resources are not provided for data (PUSCH), the terminal (1) selects a cell and/or resource on which to transmit a scheduling request, or if no resource is allocated for scheduling requests (SR) the invention allows the terminal to select a suitable uplink cell and/or signature for a random access transmission (PRACH), and/or characteristic of a signal used to request such resources. A RACH transmission may also take place if SR has been transmitted more than a defined number of times without PUSCH resources being granted. Use of the most appropriate cell/resource for the request will improve the achievable data rate and system capacity.

Claims

1. A wireless communication method in which a terminal communicates with a network via at least two cells of a plurality of cells and transmits a request for uplink resources, wherein the terminal selects at least one of:

at least one cell from among said plurality of said cells for transmission of said request,

a resource for transmission of said request from among a plurality of resources provided by a cell; and

a characteristic of a signal used to transmit said request;

wherein the selection is in dependence on at least one of;

the reason for said request;

the characteristics of an uplink channel for transmission of said request; and

the preference of the network.

2. The wireless communication method according to claim 1 further comprising:

the terminal sending said request via at least one first cell in accordance with the selection;

the network responding to said request by notifying the terminal, via at least one second cell, of a grant of resources; and

the resources being resources applying to at least one third cell.

3. The wireless communication method according to claim 2 wherein the first and second cells, and/or the second and third cells, and/or the first and third cells, are different cells.

4. The wireless communication method according to claim 2 wherein the first and second cells, and/or the second and third cells, and/or the first and third cells, include at least one cell in common.

5. The wireless communication method according to claim 1 wherein the reason for said request includes:

a requirement for uplink resources on a specific cell;

or

a lack of response to at least one previous request.

6. The wireless communication method according to claim 1 wherein the characteristics of an uplink channel for transmission of said request include at least one of:

the path loss of the uplink channel for transmission of a random access request;

the path loss of the uplink channel for transmission of a scheduling request;

the bandwidth of the cell;

resources configured in the cell for requests for uplink resources; and

expected latency in granting resources.

7. The wireless communication method according to claim 1 wherein the preference of the network includes:

a cell indicated in a configuration signalled by the network; and

/or

cells among said plurality of cells which are activated for the terminal.

8. The wireless communication method according to claim 7 wherein the at least two cells include a primary cell and a secondary cell, and the cell indicated in a configuration by the network is a secondary cell.

9. The wireless communication method according to claim 1 further comprising the terminal detecting that resources are available for a scheduling request on at least one selected cell, and transmitting a scheduling request as said request.

10. The wireless communication method according to claim 1 further comprising the terminal detecting that no resources are available for a scheduling request on a selected cell, and transmitting a random access request as said request.

11. The wireless communication method according to claim 10, applied to an LTE-compliant network and wherein the random access request is a PRACH signature, the PRACH signature selected by the terminal as one characteristic of the signal used to transmit said request.

12. The wireless communication method according to claim 11 further comprising the network configuring in advance at least one PRACH signature for use as said request.

13. A wireless communication network comprising a terminal and a plurality of base stations, the terminal arranged to communicate with the network via at least two cells of a plurality of cells and to transmit a request for uplink resources, wherein the terminal is arranged to select:

at least one cell from among said plurality of said cells for transmission of said request;

a resource for transmission of said request from among a plurality of resources provided by a cell; and

a characteristic of a signal used to transmit said request;

and to perform the selection in dependence on at least one of;

the reason for said request;

the characteristics of an uplink channel for transmission of said request; and

the preference of the network.

14. A terminal for use in a wireless communication network comprising a plurality of base stations, the terminal arranged to communicate with the network via at least two cells of a plurality of cells and to transmit a request for uplink resources, wherein the terminal is arranged to select:

at least one cell from among said plurality of said cells for transmission of said request;

a resource for transmission of said request from among a plurality of resources provided by a cell; and

a characteristic of a signal used to transmit said request;

and to perform the selection in dependence on at least one of;

the reason for said request;

the characteristics of an uplink channel for transmission of said request; and

the preference of the network.

15. A base station controlling at least one cell of a plurality of cells serving a terminal in a wireless communication network, and arranged to:

receive a request for resources from the terminal on at least one first cell;

respond to said request by notifying the terminal, via at least one second cell, of a grant of resources; and

the resources being resources on at least one third cell;

wherein the base station is arranged to select the second cell independently of the first cell.