WO2006079242A1 - Method for measuring in wcdma system - Google Patents

Abstract

The invention discloses a method for measuring in WCDMA system, which includes the following steps: obtains the position information of switching area within the band, between the band and between the system for the cell in the WCDMA system; determines the position information of the mobile station accessing to the cell; compares the position information of the mobile station with that of the switching area; opens or closes the measuring within the band, between the band and between the system on the basis of the compared result. The method for measuring in WCDMA system according to the invention could close all the measuring in association with switching, when the UE is beyond the switching area, thereby extremely alleviates the affecting to air interface by the measuring, decrease the power consumption with the UE, and extends the stand-by time of the UE, consequently, improves the performance of the entire WCDMA system expressly.

Description

 Method for measuring in WCDMA system

 The present invention relates to an improved method of measuring a wideband code division multiple access system, and more particularly to a method for controlling the opening and closing of a WCDMA system and handover related measurement using position information of a mobile station. Background technique

 The WCDMA system supports a very wide variety of measurement types, among which the correlation related to handover is mainly the measurement of the same frequency cell (intra-frequency measurement), the measurement of the inter-frequency cell (inter-frequency measurement) and the measurement of the different system cell (inter-system measurement). Kind. These measurements are the basis for intra-frequency, inter-frequency, and inter-system handovers by mobile stations (hereinafter referred to as UEs). In most cases, only those measurements are taken, and the corresponding switching can proceed smoothly. At the same time, we must see that the opening of these measurements adds extra overhead to the network, UE and airborne radio resources. In particular, inter-frequency measurement and inter-system measurement often need to open the compressed mode, and the compression mode will increase the cell. The load has a bad influence on the capacity of the cell; at the same time, the UE is limited by the volume and the battery capacity, and reducing the power consumption of the UE is also a very urgent problem. The standby time of the UE is an important indicator for evaluating the performance of the WCDMA network. Under the premise of not affecting the execution of the switching function, the opening time of various types of switching-related measurements can be reduced as much as possible, which has a beneficial effect on both the network and the UE.

 At present, there are patents related to reducing measurement overhead in WCDMA systems at home and abroad.

 The Chinese patent "Method for Switching between Different Systems in CDMA Communication System" with the application number of 021122023.4, which determines whether the quality of the active set cell is used to determine whether the compressed mode is used for inter-system measurement, although the patent can be used as needed. Turn on intersystem measurements, but in-frequency measurements always need to be turned on, not a solution that completely reduces measurement overhead.

 Chinese Patent Application No. 01144933.0, "An Inter-System Switching Method", which realizes the control of inter-system measurement by monitoring the signal quality of a cell, but it must still be turned on by intra-frequency measurement.

US Patent No. 858672, "Systems and methods for intelligent inter-system handoff", which must use an external global positioning device to accurately locate the end position for switching, but the switching is performed independently of the quality of the different systems. Therefore, the switching has a certain degree of blindness. In the European patent "Handover procedure based on position data of mobile terminal in multi-mode mobile communications system", the patent directly determines the inter-system handover by using the location information of the UE, and the UE position information is measured with high precision. If GPS is used, it will increase the cost and complexity of the measuring device. If the ordinary measuring device is used, the measurement of the beilial information is not accurate enough to meet the needs of switching between systems, which is easy to cause dropped calls. Summary of the invention

 The purpose of the present invention is to enable the measurement required by the UE to be turned on in a targeted manner by using the location information of the UE, and to turn off the measurement that the UE does not need, so as to minimize the overhead caused by the measurement to the network, the UE, and the over-the-air radio resource.

 In order to achieve the above object, the present invention provides a method of measurement in a WCDMA system, comprising the steps of:

 Step a: acquiring location information of an intra-frequency handover area, an inter-frequency handover area, and an inter-system handover area of the cell in the WCDMA system;

 Step b, determining location information of the mobile station accessing the cell;

 Step c: comparing the location information of the mobile station with the location information of the handover area; and step d, turning on or off the intra-frequency measurement, the inter-frequency measurement, and the inter-system measurement according to the comparison result. In the above method for measuring in a WCDMA system, the step b further includes: Step M, the radio network controller in the WCDMA system measures a time difference of sending and receiving of the mobile station;

 Step b2, the base station subsystem in the WCDMA system measures the loop delay of the corresponding wireless link of the mobile station, and periodically reports it to the radio network controller;

 Step b3: The radio network controller calculates location information of the mobile station according to the transceiver time difference and loop delay.

 In the above method for measuring in a WCDMA system, the step d further includes the following steps: Step dl, if the result of the comparison in the step c is that the mobile station is in the intra-frequency switching region, the intra-frequency measurement is turned on. , otherwise the intra-frequency measurement is turned off;

Step d2, if the result of the comparison in the step c is that the mobile station is in the inter-frequency switching area, the inter-frequency measurement is turned on, otherwise the inter-frequency measurement is turned off; In step d3, if the result of the comparison in the step c is that the mobile station is in the inter-system handover area, the inter-system measurement is initiated, otherwise the inter-system measurement is turned off.

 In the above method for measuring in a WCDMA system, the step a obtains the switching position information by actual road test.

 In the above method for measuring in a WCDMA system, the step a and the step b further include the steps of: the mobile station accessing the cell, and the radio network controller in the WCDMA system establishes a service for the mobile station.

 The method for measuring in the WCDMA system described above, further comprising: returning to step 13.

 In the above method for measuring in a WCDMA system, the step a and the step b further include the steps of: respectively, according to the position information of the intra-frequency switching area, the inter-frequency switching area, and the inter-system switching area, and using hysteresis parameters respectively Obtaining the position information of the intra-frequency measurement open area, the inter-frequency measurement open area, and the inter-system measurement open area, and the position information of the intra-frequency measurement closed area, the inter-frequency measurement closed area, and the inter-system measurement closed area

Λ≤, ο

 In the above method for measuring in a WCDMA system, the step b further includes: Step bl, the radio network controller in the WCDMA system measures a time difference of sending and receiving of the mobile station;

 Step b2, the base station subsystem in the WCDMA system measures the loop delay of the corresponding wireless link of the mobile station, and periodically reports it to the radio network controller;

 Step b3: The radio network controller calculates location information of the mobile station according to the transceiver time difference and loop delay.

In the above method for measuring in a WCDMA system, the step d further includes the following steps: Step dl, if the result of the comparison in the step c is that the mobile station is in the intra-frequency measurement open area, the intra-frequency is turned on. Measuring, the mobile station is in the intra-frequency measurement closed area, and the intra-frequency step d2 is turned off. If the result of the comparison in the step c is that the mobile station is in the inter-frequency measurement open area, the inter-frequency measurement is turned on. If the mobile station is in the inter-frequency measurement closed area, the inter-frequency measurement step d3 is turned off. If the result of the comparison in the step c is that the mobile station is in the inter-system measurement open area, the inter-system measurement is turned on. The inter-system measurement is turned off when the mobile station is in the inter-system measurement off zone. The method for measuring in the WCDMA system described above, further comprising: returning to step 13.

 Compared with the prior art, the method of the invention greatly shortens the opening time of the intra-frequency measurement, the inter-frequency measurement and the inter-system measurement, reduces the load of the system and the UE, increases the capacity of the system, and prolongs the UE. Standby time.

 The invention is described in detail below with reference to the accompanying drawings and specific embodiments. DRAWINGS

 1 is a schematic diagram of a handover area of a cell in a WCDMA system;

 Figure 2 is a schematic diagram of the results of different positioning methods;

 FIG. 3 is a schematic diagram of a signaling process for measuring UE location information;

 Figure 4 is a schematic diagram of a signaling flow for measuring RTT;

 Figure 5 is a flow chart of a method of measurement in a WCDMA system of the present invention. detailed description

 As shown in FIG. 1, compared with the coverage of one cell 1, the handover area 11 occupies a relatively small area. If the user moves to the edge of the cell and approaches the handover area 11, the measurement related to the handover is turned on. At the moment, the measurement is turned off, so that the user can be switched while minimizing the overhead caused by the measurement. That is, if it can be determined that the UE is not in the handover area 11, all measurements related to the handover can be turned off.

 WCDMA systems have provided a variety of methods for measuring UE location, such as cell center coordinates plus RTT (Round Trip Time) and network-assisted Global Positioning System (A-GPS) positioning methods. Different methods have different positioning accuracy. As shown in Fig. 2, the A-GPS positioning method has high precision and can be located in a certain polygonal area 3 with a small range. However, the method has a large overhead and is complicated to calculate; The RTT method has low accuracy and can only be located within a certain ring 4 with a radius d from the center of the cell. However, the method is simple, basically does not require the participation of the UE, and can also meet the requirements of position measurement. By using the cell center coordinate plus RTT method, it can be determined that at least the UE is located on a certain ring 4 centered on the center of the cell.

The location of the handover area of the cell in the WCDMA system can be obtained by actual road test, and the form can be in the form of a polygonal connection or a circular form indicated by a radius, and is stored in a database at the same time. By comparing the location of the UE with the location of the handover area, a decision can be made to turn the measurement associated with the handover on or off.

 The invention adopts the method of cell center coordinate plus RTT to determine the location of the mobile station. The principle of the positioning method is to measure the time difference of the UE transceiving data UE Rx_Tx time difference type 2 (hereinafter abbreviated as UE Rx_Tx) and Node B (the station station) System) Corresponding to the loop delay RTT of the radio link, determining the distance d value between the UE and the cell antenna center position according to the following formula:

 d 2 c X (RTT-UE Rx_Tx) 12 (Equation 1) where c is the speed of light.

 As shown in Figure 2, due to the influence of measurement error, the error range of d is approximately plus or minus 35 meters. Therefore, for each cell, the UE is located somewhere inside the ring 4 centered on the transmitting antenna and having a radius of d + 35 m and d - 35 m.

 The UE Rx_Tx of the UE is determined. Therefore, as long as the UE Rx_Tx is measured once, the location of the UE can be determined only by measuring the RTT, and the measurement of the RTT is performed at the Node B without occupying the empty resources.

 The UE sends and receives data time difference UE x — Tx through the radio network controller (RNC: Radio

The network controller is measured by the UE. The signaling process is as shown in Figure 3. First, the RNC sends a "MEASUREMENT CONTROL" signaling to the UE. The UE returns the MEASUREMENT with the time difference of the receiving and receiving data UE Rx-Tx according to the received signaling command. REPORT".

 The RTT measurement is performed at Node B. The signaling flow is shown in Figure 4. First, the RNC sends a "DEDICATED MEASUREMENT INITIATION EQUEST" message to NODE B. The NODE B period measurement RTT is sent. NODE B sends a "DEDICATED MEASUREMENT INITIATION RESPONSE" message to the RNC. The establishment of this dedicated measurement. The NODE B then reports the RTT measurement via the "DEDICATED MEASUREMENT REPORT" cycle.

 The method flow of the measurement in the WCDMA system of the present invention is as shown in FIG. 5, and includes the following steps: Step 501: During the network planning, the intra-frequency handover area and the inter-system handover are obtained by using the actual road test result. Location information of the zone, and saved in the database;

 Step 502: Waiting for the mobile station to access;

Step 503: The new mobile station access system RNC establishes a service for the mobile station to camp on the cell. Step 504: The RC obtains the UE transceiver time difference UE Rx_Tx by measuring the UE _.

Step 505: The RNC turns on the dedicated measurement of the Node B, and measures the ring of the corresponding wireless link of the user. Road delay RTT;

 Step 506: The RNC receives the period of the Node B and reports the RTT.

 Step 507: The RNC calculates the location where the UE is located by combining the UE Rx_Tx and the RTT. Step 508: Compare the location of the UE with the location of the intra-frequency handover zone saved by the database.

 If the UE is in the intra-frequency handover zone and the UE intra-frequency measurement is not turned on, the intra-frequency measurement is turned on, and the process proceeds to step 509;

 If the UE is in the intra-frequency handover area and the UE intra-frequency measurement is turned on, proceed to step 509;

 If the UE is not in the intra-frequency handover zone and the UE intra-frequency measurement is turned on, the intra-frequency measurement is turned off, and the process proceeds to step 509;

 If the UE is not in the intra-frequency handover area and the UE intra-frequency measurement is not turned on, go to step 509; Step 509: Compare the UE location with the inter-frequency handover area saved by the database,

 If the UE is in the inter-frequency handover area and the UE inter-frequency measurement is not turned on, the inter-frequency measurement is turned on, and the process proceeds to step 510;

 If the UE is in the inter-frequency handover area and the UE inter-frequency measurement is turned on, proceed to step 510;

 If the UE is not in the inter-frequency handover area and the UE inter-frequency measurement is turned on, the inter-frequency measurement is turned off, and the process proceeds to step 510;

 If the UE is not in the inter-frequency handover area and the UE inter-frequency measurement is not turned on, go to step 510; Step 510: Compare the UE location with the location of the inter-system handover area saved by the database,

 If the UE is in the inter-system handover area and the inter-system system measurement is not turned on, the inter-system measurement is turned on, and the process returns to step 502;

 If the UE is in the inter-system handover area and the UE inter-system measurement is turned on, then return to step 502; if the UE is not in the inter-system handover area and the UE inter-system measurement is turned on, the inter-system measurement is turned off, and the process returns to step 502;

 If the UE is not in the inter-system handover area and the UE inter-frequency measurement is not turned on, then return to step 502. At the same time, considering that the measured position information has certain errors, the measurement related to the switching itself takes a certain time to complete, and the like, the present invention introduces hysteresis parameters, intra-frequency/inter-frequency/system when performing position information comparison. Inter-switching zone position information combined with two hysteresis parameters of intra-frequency/inter-frequency/inter-system measurement on and off, respectively, can be used to obtain intra-frequency/inter-frequency/inter-system measurement open area and intra-frequency/inter-frequency/inter-system measurement closed area. s position.

Correspondingly, in the flow shown in FIG. 5, if the UE is in the intra-frequency/inter-frequency/inter-system measurement open area, The intra-frequency/inter-frequency/inter-system measurement is turned on accordingly, and the intra-frequency/inter-frequency/inter-system measurement is turned off if the UE is in the intra-frequency/inter-frequency/inter-system measurement off zone.

 The introduction of the hysteresis parameter ensures that the measurement related to the switching is opened in advance when entering the switching area, and the relevant measurement is turned off after leaving the switching area.

 At the same time, the two hysteresis parameters can be set differently to avoid frequent switching on and off related to the switching. Different hysteresis parameters can be set for intra-frequency, inter-frequency and inter-system measurements as needed.

 Of course, the present invention may be embodied in various other various modifications and changes without departing from the spirit and scope of the invention. Changes and modifications are intended to be included within the scope of the appended claims. Industrial applicability

 The method for measuring in the WCDMA system of the present invention can turn off all measurements related to handover when the UE is not in the handover area, thereby minimizing the influence of the measurement on the air interface, reducing the power consumption of the UE, and prolonging the standby of the UE. Time, the improvement of the entire WCDMA system.

Claims

Claim A method of measurement in a WCDMA system, comprising the steps of:  Step a: acquiring location information of an intra-frequency handover area, an inter-frequency handover area, and an inter-system handover area of the cell in the WCDMA system;  Step b, determining location information of the mobile station accessing the cell;  Step c: comparing the location information of the mobile station with the location information of the handover area; and step d, turning on or off the intra-frequency measurement, the inter-frequency measurement, and the inter-system measurement according to the comparison result. 2. The method of measuring in a WCDMA system according to claim 1, wherein the step b further comprises:  Step bl, the radio network controller in the WCDMA system measures the time difference of sending and receiving of the mobile station;  Step b2, the base station subsystem in the WCDMA system measures the loop delay of the corresponding wireless link of the mobile station, and periodically reports it to the radio network controller;  Step b3: The radio network controller calculates location information of the mobile station according to the transceiver time difference and loop delay.  The method of measuring in a WCDMA system according to claim 1 or 2, wherein the step d further comprises the following steps:  Step dl, if the result of the comparison in the step c is that the mobile station is in the intra-frequency switching area, the intra-frequency measurement is turned on, otherwise the intra-frequency measurement is turned off;  Step d2, if the result of the comparison in the step c is that the mobile station is in the inter-frequency switching area, the inter-frequency measurement is turned on, otherwise the inter-frequency measurement is turned off;  In step d3, if the result of the comparison in the step c is that the mobile station is in the inter-system switching area, the inter-system measurement is turned on, otherwise the inter-system measurement is turned off.  A method of measuring in a WCDMA system according to claim 3, wherein said step a acquires said switching position information by actual road test.  The method of measuring in a WCDMA system according to claim 1 or 2, wherein the step a and the step b further comprise the steps of: the mobile station accessing the cell, the wireless in the WCDMA system A network controller establishes a service for the mobile station. 6. The method of measuring in a WCDMA system according to claim 3, further comprising Including the steps: Return to step 13.  The method of measuring in a WCDMA system according to claim 1, wherein the step (a) and the step b further comprise the step of: switching between the intra-frequency switching area, the inter-frequency switching area, and the system. The position information of the area and the hysteresis parameters are used to obtain the position information of the intra-frequency measurement open area, the inter-frequency measurement open area, and the inter-system measurement open area, and the intra-frequency measurement closed area, the inter-frequency measurement closed area, and the inter-system measurement closed area. information.  8. The method of measuring in a WCDMA system according to claim 7, wherein the step b further comprises:  Step bl, the radio network controller in the WCDMA system measures the time difference of sending and receiving of the mobile station;  Step b2, the base station subsystem in the WCDMA system measures the loop delay of the corresponding wireless link of the mobile station, and periodically reports it to the radio network controller;  Step b3: The radio network controller calculates location information of the mobile station according to the transceiver time difference and loop delay.  The method of measuring in a WCDMA system according to claim 7 or 8, wherein the step d further comprises the following step - step d1, if the result of the comparison in the step c is that the mobile station is in frequency If the intra-frequency measurement is turned on, the intra-frequency measurement is turned on, and the mobile station is in the intra-frequency measurement closed area, and the intra-frequency step d2 is turned off. If the result of the comparison in the step c is that the mobile station is in the inter-frequency Measuring the open area, the inter-frequency measurement is turned on, and the mobile station is in the inter-frequency measurement closed area, and the inter-frequency measurement is turned off;  Step d3: If the result of the comparison in the step c is that the mobile station is in the inter-system measurement open area, the inter-system measurement is turned on, and the mobile station is in the inter-system measurement closed area to close the inter-system measurement.  10. The method of measuring in a WCDMA system according to claim 9, further comprising the step of: returning to the step