Optimized random access channel (RACH) access

• US 8,526,986 B2
• Filed: 02/05/2008
• Issued: 09/03/2013
• Est. Priority Date: 02/07/2007
• Status: Active Grant

• Current Assignee: LG Electronics, Inc. (LG Corporation)
• Original Assignee: LG Electronics, Inc. (LG Corporation)
• Inventors: Fischer, Patrick, Feuillette, Remi
• Primary Examiner(s): Pan, Yuwen
• Assistant Examiner(s): Woodall, Mark
• Application Number:
  US12/526,035
• Publication Number:
  US 20100323736A1
• Time in Patent Office: 2,037 Days
• Field of Search: 455/502, 455/511, 455/514, 455/515, 455/517, 370/312, 370/466, 370/467, 370/469, 370/470, 370/254, 370473-475
• US Class Current: 455/511
• CPC Class Codes: H04W 28/06 Optimizing the usage of the radio link, e.g. header compression, information sizing , discarding information system modifying transmission characteristic according to link quality by modifying frame length H04L1/0007; dynamic adaptation of the packet size for flow control or congestion control H04L47/365
• CPC Class Codes: H04W 74/004 in the uplink, i.e. towards network
• CPC Class Codes: H04W 74/0833 Random access procedures, e.g. with 4-step access
• CPC Class Codes: H04W 74/0866 using a dedicated channel for access
• CPC Class Codes: H04W 8/26 Network addressing or numbering for mobility support
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

A method and apparatus to reduce the overhead related to allocation of the terminal identifier in a random access procedure and an optimized method for detecting a collision are provided. By allocating a “short” terminal identifier in the Random Access Response that is identifiers and allocating the permanent terminal identifier at the end of the random access procedure, the size of data that must be transmitted in the Random Access Response is reduced and power is saved.

Claims

1. A method of a mobile terminal for establishing a communication link between the mobile terminal and a network, the method comprising:

transmitting, from the mobile terminal, a random access request to the network for initiating a random access procedure to establish the communication link between the mobile terminal and the network;

receiving a random access response acknowledging receipt of the random access request, the random access response comprising a short mobile terminal identifier, wherein the short mobile terminal identifier is selected from a subset of short C-RNTIs (Cell-Radio Network Temporary Identifier) having a size smaller than 16 bits, wherein a size of the short C-RNTI is indicated by system information;

forming, at the mobile terminal, a mobile terminal identifier from the short mobile terminal identifier comprised in the received random access response, wherein the mobile terminal identifier is a C-RNTI that provides a unique mobile terminal identification at a cell level; and

transmitting, from the mobile terminal, a scheduled uplink data and the formed mobile terminal identifier to the network.

2. The method of claim 1, wherein the size of the short C-RNTI is 8-bits.

3. The method of claim 1, wherein the short mobile terminal identifier is appended at a least significant bit (LSB) of the mobile terminal identifier.

4. A method of a network for establishing a communication link between a mobile terminal and the network, the method comprising:

receiving, by the network, a random access request for initiating a random access procedure to establish the communication link between the mobile terminal and the network;

transmitting, by the network, a random access response acknowledging receipt of the random access request to the mobile terminal, the random access response comprising a short mobile terminal identifier, wherein the short mobile terminal identifier is selected from a subset of short C-RNTIs (Cell-Radio Network Temporary Identifier) having a size smaller than 16 bits, wherein a size of the short C-RNTI is indicated by system information, wherein a mobile terminal identifier is formed from the short mobile terminal identifier, and the mobile terminal identifier is a C-RNTI that provides a unique mobile terminal identification at a cell level; and

receiving, by the network, a scheduled uplink data and the formed mobile terminal identifier.

5. A mobile terminal for establishing a communication link between the mobile terminal and a network, the mobile terminal comprising:

a transmitting unit that transmits a random access request to the network for initiating a random access procedure to establish the communication link between the mobile terminal and the network;

a receiving unit that receives a random access response acknowledging receipt of the random access request, the random access response comprising a short mobile terminal identifier, wherein the short mobile terminal identifier is selected from a subset of short C-RNTIs (Cell-Radio Network Temporary Identifier) having a size smaller than 16 bits, wherein a size of the short C-RNTI is indicated by system information;

a display unit that displays visual information;

an input unit that receives inputs; and

a processing unit that forms a mobile terminal identifier from the short mobile terminal identifier comprised in the received random access response, wherein the mobile terminal identifier is a C-RNTI that provides a unique mobile terminal identification at a cell level,

wherein the transmitting unit further transmits a scheduled uplink data and the formed mobile terminal identifier to the network.

6. The mobile terminal of claim 5, wherein the short mobile terminal identifier is appended at a least significant bit (LSB) of the mobile terminal identifier.

7. A network for establishing a communication link with a mobile terminal, the network comprising:

a receiver that receives a random access request for initiating a random access procedure to establish the communication link between the mobile terminal and the network; and

a transmitter that transmits a random access response acknowledging receipt of the random access request, the random access response comprising a short mobile terminal identifier, wherein the short mobile terminal identifier is selected from a subset of short C-RNTIs (Cell-Radio Network Temporary Identifier) having a size smaller than 16 bits, wherein a size of the short C-RNTI is indicated by system information, wherein a mobile terminal identifier is formed from the short mobile terminal identifier, and the mobile terminal identifier is a C-RNTI that provides a unique mobile terminal identification at a cell level,

wherein the receiver further receives a scheduled uplink data and the mobile terminal identifier.

8. The network of claim 7, wherein the short mobile terminal identifier is appended at a least significant bit (LSB) of the selected mobile terminal identifier.