Reference signal transmission scheduling device and reference signal transmission scheduling method

• US 8,737,335 B2
• Filed: 06/14/2010
• Issued: 05/27/2014
• Est. Priority Date: 06/19/2009
• Status: Active Grant

• Current Assignee: KDDI Corporation
• Original Assignee: KDDI Corporation
• Inventors: Konishi, Satoshi, Wang, Xiaoqiu, Komine, Toshihiko
• Primary Examiner(s): Nguyen, Brian D
• Assistant Examiner(s): NGUYEN, TOAN D
• Application Number:
  US13/378,177
• Publication Number:
  US 20120106489A1
• Time in Patent Office: 1,443 Days
• Field of Search: 370/328, 370/329, 370/341, 370/348, 375/298, 455/69, 455/450
• US Class Current: 370/329
• CPC Class Codes: H04W 72/0453 Resources in frequency domain, e.g. a carrier in FDMA
• CPC Class Codes: H04W 72/51 based on terminal or device properties

Abstract

A reference signal transmission scheduling device, which performs scheduling on uplink transmission of a reference signal (SRS) from a mobile terminal to a base station in a wireless communication system, is designed to appropriately allocate an SRS transmission resource to the mobile terminal in consideration of the current circumstances of the mobile terminal. Herein, the maximum value of an SRS bandwidth is calculated based on the maximum transmission-enabled power of the mobile terminal, while the minimum value of the SRS bandwidth is calculated based on the mobility of the mobile terminal. Additionally, the SRS bandwidth, which is actually used by the mobile terminal subjected to SRS transmission resource allocation, is determined within the range between the maximum value and the minimum value of the SRS bandwidth.

Claims

1. A reference signal transmission scheduling device that performs scheduling on uplink transmission of a reference signal (SRS) from a mobile terminal to a base station in a radio communication system, said reference signal transmission scheduling device comprising:

a maximum SRS bandwidth determination part that calculates a maximum value of an SRS bandwidth based on a maximum transmission-enabled power of the mobile terminal;

a minimum SRS bandwidth determination part that calculates a minimum value of the SRS bandwidth based on a mobility of the mobile terminal; and

an SRS transmission resource allocation part that determines the SRS bandwidth, which is actually used by the mobile terminal subjected to SRS transmission resource allocation, within a range between the maximum value and the minimum value of the SRS bandwidth.

2. The reference signal transmission scheduling device according to claim 1, wherein the SRS transmission resource allocation part allocates an SRS transmission resource to the mobile terminal only when the SRS bandwidth is defined within the range between the maximum value and the minimum value with respect to the mobile terminal subjected to SRS transmission resource allocation.

3. The reference signal scheduling device according to claim 1, wherein the SRS resource is allocated to the mobile terminal by use of the maximum value of the SRS bandwidth when the maximum value of the SRS bandwidth decreases to be lower than the minimum value.

4. The reference signal transmission scheduling device according to claim 1, wherein the SRS transmission resource allocation part sequentially selects values of the SRS bandwidth, within the range defined between the maximum value and the minimum value of the SRS bandwidth, in ascending order or descending order.

5. The reference signal transmission scheduling device according to claim 1, wherein the SRS transmission resource allocation part selects a desired SRS transmission resource from among available SRS transmission resources within the range defined between the maximum value and the minimum value of the SRS bandwidth such that a residue of the same SRS transmission resource is maximized or minimized.

6. The reference signal transmission scheduling device according to claim 1 further comprising an allowable mobility determination table that determines an allowable mobility with respect to a pair of an SRS transmission interval and the SRS bandwidth.

7. The reference signal transmission scheduling device according to claim 1 further comprising an SRS transmission interval determination part that determines an SRS transmission interval based on a number of mobile terminals whose mobility is below a predetermined mobility threshold.

8. The reference signal transmission scheduling device according to claim 6, wherein the SRS transmission interval determination part determines the SRS transmission interval based on a ratio and a number of mobile terminals whose mobility is below the predetermined mobility threshold.

9. A reference signal transmission scheduling method that performs scheduling on uplink transmission of a reference signal (SRS) from a mobile terminal to a base station in a radio communication system, said reference signal transmission scheduling method comprising:

calculating a maximum value of an SRS bandwidth based on a maximum transmission-enabled power of the mobile terminal;

calculating a minimum value of the SRS bandwidth based on a mobility of the mobile terminal; and

determining the SRS bandwidth, which is actually used by the mobile terminal subjected to SRS transmission resource allocation, within a range between the maximum value and the minimum value of the SRS bandwidth.

10. A non-transitory computer program implementing a reference signal transmission scheduling process for performing scheduling on uplink transmission of a reference signal (SRS) from a mobile terminal to a base station in a radio communication system, said computer program comprising:

calculating a maximum value of an SRS bandwidth based on a maximum transmission-enabled power of the mobile terminal;

calculating a minimum value of the SRS bandwidth based on a mobility of the mobile terminal; and

determining the SRS bandwidth, which is actually used by the mobile terminal subjected to SRS transmission resource allocation, within a range between the maximum value and the minimum value of the SRS bandwidth.