Direct amplifying station and positioning method for mobile station thereof

• US 20050153653A1
• Filed: 01/27/2003
• Published: 07/14/2005
• Est. Priority Date: 04/26/2002
• Status: Active Grant

• Current Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Original Assignee: Huawei Technologies Co., Ltd. (Huawei Investment & Holding Co., Ltd.)
• Inventors: Du, Jiancheng, Diao, Xinxi
• Granted Patent: US 7,283,787 B2
• Time in Patent Office: Days
• US Class Current: 455/11.100
• CPC Class Codes: H04B 7/155 Ground-based stations H04B7/204 takes precedence
• CPC Class Codes: H04W 16/26 Cell enhancers or enhancement, e.g. for tunnels, building shadow

Abstract

“The present invention relates to a repeater for positioning mobile station and a method thereof. The repeater according to the present invention is implemented through adding a cell identifier generator module to the downlink circuit structure of a conventional repeater; said cell identifier generator module includes: a synchronization searching unit designed to search for base station synchronization signal, a time delay unit designed to generate a fixed delay between start time of cell identifier signal frame and start time of base station pilot signal frame, and a cell identifier signal generating unit designed to generate cell identifier signal code word. The mobile station positioning method determines the mobile station is in the coverage of the repeater on the basis that the time difference between base station pilot signal and cell identifier signal is consistent to the fixed delay; then the method utilizes TOA (Time of Arrival) measuring function to determine the distance from the mobile station to the repeater; thus it improves positioning accuracy of mobile stations in the coverage of the repeater. The repeater for positioning mobile station is easy to implement and can meet the positioning requirement of a plurality of mobile stations in the coverage of the repeater.”

Claims

1. A repeater, wherein a cell identifier generator module is added to downlink circuit structure of said repeater, said cell identifier generator module comprising:

a synchronization searching unit for searching for a synchronization signal of a base station, a time delay unit for generating a fixed delay between a frame start time of a cell identifier signal and a frame start time of a base station pilot signal, and a cell identifier signal generating unit for generating a cell identifier signal code word;

said time delay unit generating the fixed delay according to the searching result of the synchronization searching unit.

2. A repeater according to claim 1, wherein:

an input end of said cell identifier generator module is connected to a low-noise amplifier module of the repeater, and an output end of said cell identifier generator module is connected to a power amplifier module of the repeater via a coupler.

3. A repeater according to claim 2, wherein said cell identifier generator module also comprises:

a down-conversion unit, an A/D (Analog to Digital) conversion unit, a D/A (Digital to Analog) conversion unit, a, up-conversion unit, and a filtering unit;

wherein said down-conversion unit is designed to carry out frequency conversion from RF to intermediate frequency for received signals;

said A/D conversion unit is designed to carry out sampling and quantification for intermediate frequency signals;

said D/A conversion unit is designed to carry out D/A conversion to obtain a base-band form of the cell identifier signal;

said up-conversion unit is designed to carry out conversion from base-band to RF for the cell identifier signal;

said filtering unit is designed to carry out band restriction for the cell identifier signal to control frequency leakage to adjacent frequency;

said cell identifier signal is coupled to an input end of the power amplifier in the downlink circuit structure of the repeater via said D/A unit, up-conversion unit, and filtering unit.

4. A method for positioning mobile station, comprising:

(1) Issuing a cell identifier signal code word, fixed delay, and search window width for the mobile station according to a positioning request of the mobile station;

(2) The mobile station utilizing a TDOA (Time Difference Of Arrival) measuring function to measure TDOAs of a cell identifier signal and a base station pilot signal and reporting the measured data;

(3) Determining whether there is a time difference consistent to a fixed delay between the cell identifier signal and the base station pilot signal according to the reported data from the mobile station;

if so, going to step (4);

otherwise going to step (7);

(4) Reading calibrated value TOA_c of TOA (Time Of Arrival) between a repeater and the base station, and initiating an RTT (Round Trip Time) measuring function of the base station to measure RTT of the mobile station, wherein TOA_c=(½

) RTT;

(5) Converting the measured RTT reported from the base station into measured value TOA_m of TOA, wherein TOA_m=(½

) RTT, which is the TOA from the mobile station to the base station via the repeater, subtracting the calibrated value TOA_c of TOA from the repeater to the base station from TOA_m and taking the result as TOA TOA_trans from the mobile station to the repeater, wherein TOA_trans=TOA_m −

TOA_c;

(6) Calculating distance between the mobile station and the repeater through multiplying TOA_trans with light velocity; and

(7) Determining position of the mobile station with the mobile station positioning method.

5. A method for positioning mobile station according to claim 4, wherein said cell identifier signal is a scrambling code of the base station, which is different from that of adjacent base stations.

6. A method for positioning mobile station according to claim 4, wherein said mobile station positioning method in step (7) is TDOA positioning method.

7. A method for positioning mobile station according to claim 4, wherein said mobile station positioning method in step (7) is TOA positioning method.