WO2007143927A1

WO2007143927A1 - Access method of terminal device and system

Info

Publication number: WO2007143927A1
Application number: PCT/CN2007/001800
Authority: WO
Inventors: Mingxia Xu
Original assignee: Huawei Technologies Co., Ltd.
Priority date: 2006-06-06
Filing date: 2007-06-06
Publication date: 2007-12-21
Also published as: CN101047990A

Abstract

An access method of terminal device and system are provided. The method includes: Network sends a paging message to terminal device, and the paging message includes orthogonal code information to assign terminal device. According to orthogonal code terminal device modulates access probe, sends the access probe to network, and accesses to network. When terminal device answers the paging, the used orthogonal code is assigned by network, it differs from other used orthogonal code by terminal device of answering the paging, and also differs from other used orthogonal code by terminal device of initiating call. This ensures that used orthogonal code by terminal device of answering the paging does not conflict with other used orthogonal code by terminal device.

Description

Terminal device access method and system

The present invention relates to the field of communications, and in particular, to a terminal device access method and system. Background technique

In the wireless communication system, since the uplink access channel is a single shared channel, and each terminal device can randomly initiate the access process according to its own will, if two or more terminal devices simultaneously send the access information The signal of the spatial interface will be confused, which will cause the receiving end to not correctly demodulate the originating signal. This is called the collision of random access.

The random access method is a process of initiating access by means of a probe. In order to reduce the collision, the content of the probe can be modulated by mutually orthogonal code groups, and the random access of different terminal devices is modulated by different orthogonal codes, so that even if the random access message is simultaneously transmitted, the terminal can be correctly received. receive. However, different terminal equipments using the same orthogonal code modulation will cause mutual interference, and the useful information cannot be solved at the receiving end. Therefore, in order to improve the performance of random access, it is necessary to avoid the terminal device selecting the same orthogonal code at the same transmission time.

In a wireless communication system, the random access initiated by the terminal device has different cause values, and the most important ones are: responding to the paging and the initial call of the terminal device. Paging means that the remote terminal device calls the terminal device in the wireless communication system, that is, the terminal device in the wireless communication system makes a call. Since the link from the far-end to the network side has been established, the requirements for the access delay are higher than those for the terminal device under the same conditions. According to the different reason values of the random access initiated by the terminal device, the conflict between the terminal device that is simultaneously called by the different terminal device and the terminal device that is called, and the conflict between the terminal devices that start the call may be performed.

There are many ways to generate orthogonal codes, such as Walsh sequences, Golay sequences, and so on. A Walsh code is a set of code sequences consisting of 0, 1, or 1, -1, with a length of 2 to the power of n. Once the dimensions of the Walsh code are determined, the combination of all Walsh codes is determined. For example, there are 102 ⁴ types of Walsh codes in 1024 dimensions. The same code sequence, each sequence is also 1024 bits in length, which can be called 1024 code spaces, and each two code sequences are orthogonal.

Since most wireless systems currently send paging messages according to location areas, and a location area contains multiple BTSs, paging messages for one terminal device are sent in all sectors under the jurisdiction of the location area. Therefore, the paging message sent in one sector does not respond to the paging in the local cell because the terminal device is in another cell. As shown in FIG. 1, it is a paging according to the location area. The paging of AT 1 is sent in the entire location area, and AT 1 may only respond to the paging in BTS C, that is to say, there is no response paging of AT 1 in each sector of BSC A and BSC B. Come up. Of course, it is also possible that AT 1 cannot respond to paging in BTS C due to poor radio propagation conditions and the like. If the wireless system is paging by sector, each sector only pages the terminal equipment residing in the cell, and in most cases the terminal equipment will respond to the paging.

In the existing random access scheme, the content of the access probe is modulated using a 1024-dimensional Walsh code. The index number of 1024 code spaces is 0 - 1023 , and the reservation with index number 0 - 17 is used for switching, power control and time correction of the active set. The index number 18 - 1023 (1006 total) is reserved for the access terminal (AT) to send access probes. The transmitted access probe includes probes that respond to the cause of the paging and AT originating call.

In this scheme, the Walsh code space dedicated to transmitting access probes is divided into 9 groups, and the parameters sent in the access network (AN) determine the manner of grouping. In a given grouping mode, according to the power level of the pilot and the number of bits to be transmitted on the reverse traffic channel, the group number that should be selected is jointly determined, and a Walsh code is randomly selected in the group to randomly transmit the current Probe. The Walsh code is reselected before each probe is sent, as shown in Figure 2, which is the Walsh code allocation method in this scheme.

In the forward direction, each superframe contains one Preamble and 24 frames. Each two superframes can send a paging packet in the Preamble, and the paging packet can contain up to 8 quick paging messages. In the reverse direction, a total of four frames per medium superframe spacing allows the transmission of random access probes, as shown in Figure 3, which is the superframe structure in this scheme. Because the prior art is that all terminal devices that want to initiate random access select the same orthogonal code to select a collision according to the same algorithm; it is also difficult to avoid that the terminal device is in response to the paging, which is There is a schematic diagram of collision between response paging messages and response paging and initial call messages of different terminal devices at the same time in the technology. In this way, the terminal device that responds to the paging needs to send multiple probes to access the system, increasing the delay in responding to the paging, and affecting the performance of the paging. Summary of the invention

The embodiments of the present invention provide a method and a system for accessing a network by a terminal device in response to paging, which are used to solve the problem that a terminal device that responds to paging in the prior art may generate a collision and increase response paging. Delay, affecting paging performance issues.

A terminal device access method includes:

The network side sends a paging message to the terminal device, where the paging message carries orthogonal code information indicating the use of the terminal device;

The terminal device acquires a corresponding orthogonal code according to the orthogonal code information, and modulates the access probe according to the orthogonal code;

The terminal device sends the access probe to the network side to perform network access.

A terminal device access system, including a network side for accessing a terminal,

The network side is configured with:

The orthogonal code information setting unit is configured to set, in the paging message sent by the network side to the terminal device, the orthogonal code information used by the terminal device.

In the solution of the embodiment of the present invention, when the terminal device responds to the paging, the orthogonal code used by the terminal device is allocated by the network side, and is different from the orthogonal code used by other terminal devices that respond to the paging, and is also associated with other terminal devices that initiate the initial call. The orthogonal codes used are different, so that the orthogonal codes used by the terminal devices responding to the paging must not collide with the orthogonal codes used by other terminal devices. DRAWINGS

1 is a schematic diagram of paging by location area in the prior art;

2 is a schematic diagram of a Walsh code allocation manner in the prior art;

3 is a schematic diagram of a superframe structure in the prior art;

4 is a schematic diagram of a collision between a response paging message and a response paging and an initial call message of different terminal devices at the same time in the prior art;

Figure 5 is a schematic flowchart of Embodiment 1 of the present invention;

6 is a schematic diagram of a network side-to-side terminal transmitting a paging message carrying an orthogonal code indication according to Embodiment 1 of the present invention;

7 is a schematic flow chart of Embodiment 2 of the present invention;

8 is a schematic flowchart of Embodiment 3 of the present invention;

FIG. 9 is a schematic structural diagram of a system according to Embodiment 4 of the present invention. detailed description

Specific embodiments of the present invention are described below in conjunction with the drawings.

Example 1

As shown in FIG. 5, it is a schematic flowchart of Embodiment 1 of the present invention. It can be seen from the figure that the following steps are mainly included:

S510: The network side sends a paging message to the terminal device, where the paging message carries orthogonal code information used by the terminal.

In the terminal access process, the network side sends a paging message to the terminal device. In the solution of the first embodiment of the present invention, the paging message carries the positive terminal of the network side for modulating the access probe. Cross-code information, such as orthogonal code index.

The orthogonal code information may also be the orthogonal code itself, so that the network side may send the orthogonal code to the terminal through the paging message, or may use the orthogonal code to process the paging message when the network side sends the paging message. Than Such as scrambling or modulation processing, such that the terminal device receiving the paging can obtain the orthogonal code information that can be used while receiving the paging by matching or de-processing.

The embodiment of the present invention may allocate a part of resources in all available orthogonal codes to be specifically provided to the terminal device that responds to the paging, and use the corresponding number of bits to represent the index number of each orthogonal code, which is responsible for the network side. Resource allocation and maintenance of status. The network element responsible for maintenance may be a base station controller

(BSC), Base Transceiver Station (BTS) or Visit Location Register (VLR).

In this way, the terminal device modulates the access probe by using the orthogonal code corresponding to the orthogonal code index number in the paging message when receiving the paging message.

Taking the 802.20 system as an example, a total of 1006 Walsh codes with index numbers 18 - 1023 are used for random access, and 64 Walsh codes can be allocated for terminal devices that respond to paging. This is just one embodiment, and the actual system can be adjusted to other values as needed. Since 2 ⁶ = 64, the index number of 64 Walsh codes can be represented by 6 bits, as shown in Table 1:

Table 1: 6-bit correspondence Table of 64 different Walsh code groups

In the above step S510, the network side may also set a plurality of common timers (one timer for each paging message, and the threshold of the timer may be set according to actual conditions). When the network side receives the paging message, a field is added after each paging message to indicate the index number of the orthogonal code available to the terminal device, and a timer is started, and the index number is no longer allocated to other Used for terminal equipment.

Taking the Walsh code of each sector in the BTS as an example, the state of these Walsh code index numbers is maintained in the BTS. Initially, the status of all Walsh index numbers is "idle", as shown in Table 2:

Walsh code state Walsh code state Walsh code state Walsh code state Index number index number index number index number

000000 Idle 010000 Idle 100000 Idle 110000 Idle

000001 Idle 010001 Idle 100001 Idle 110001 Idle

000010 idle 010010 idle 100010 idle 110010 idle

000011 idle 010011 idle 100011 idle 110011 idle

000100 idle 010100 idle 100100 idle 110100 idle

000101 idle 010101 idle 100101 idle 110101 idle

000110 idle 010110 idle 100110 idle 110110 idle

000111 idle 010111 idle 100111 idle 110111 idle

001000 Idle 011000 Idle 101000 Idle 111000 Idle

001001 Idle 011001 Idle 101001 Idle 111001 Idle

001010 Idle 011010 Idle 101010 Idle 111010 Idle

001011 Idle 011011 Idle 101011 Idle 111011 Idle

001100 Idle 011100 Idle 101100 Idle 111100 Idle

001101 idle 011101 idle 101101 idle 111101 idle

001110 idle 011110 idle 101110 idle 111110 idle

001111 Idle 011111 Idle 101111 Idle 111111 Idle

Table 2 Walsh code index number status table

When the BTS receives the paging message sent by the network side, it selects an index number of the "idle" state from the above table, adds the index number to the paging message, and sets the state of the index number to "occupied. ", broadcast this paging message after starting the timer. When the BTS receives another paging message from the network side, it selects an idle index number from the above table and assigns it to the terminal device.

S520. The terminal device selects an orthogonal code according to the orthogonal code information carried in the paging message, and modulates the access probe by using the orthogonal code.

After receiving the paging message, the terminal finds a corresponding orthogonal code according to the orthogonal code information carried in the paging message, and modulates the access probe by using the orthogonal code.

S530. The terminal device sends the access probe to the network side to perform network access.

S540. The network side cancels the orthogonal code used by the terminal device according to the threshold set by the timer. Unavailable status.

Before the timer expires, after receiving the message that the terminal device responds to the paging, the network side sets the orthogonal code state used by the terminal device to "idle", and clears the timer and releases the corresponding timer; If the timer does not receive the message that the terminal device responds to the paging, the network side sets the orthogonal code state used by the terminal device to "idle, and simultaneously clears the timer and releases the corresponding timer. .

Generally, each terminal device sends 2-3 random access probes to be correctly received by the receiving end, that is, most cases can be correctly received by the receiving end within one superframe (the same terminal device that responds to the paging) The multiple random access probes all use the same Walsh code, and the timer can be set to 4 superframes (in this case, allocating 64 Walsh codes to the terminal device responding to the paging is sufficient). After the receiving end correctly solves the random access probe of the terminal device, the index number of the Walsh code assigned to the terminal device in the paging message is immediately changed to "idle" in the above table, so as to prepare for other The paging message is used, and the timer is cleared and then released, and then this timer can be used for other paging messages. If the corresponding random access probe is not received after the timeout, the Walsh code index number is forcibly released, and the BTS will modify the state of the Walsh code assigned to the terminal device in the paging message in the above table. It is "idle," in order to prepare for other paging messages, and the timer is cleared and then released, after which the timer can be used for other paging messages.

In the step S510 of the foregoing Embodiment 1, the orthogonal code of the modulation access pin can also be obtained by combining or changing the orthogonal code information with other information, such as the orthogonal code and the pilot received by the terminal device. The strength is related to, or related to, the location of the paging identification number of the terminal device in the paging message. It may also be related to a formula derived from the combination or deformation of the two.

In the first embodiment, the Walsh code is taken as an example for description, and the orthogonal code for other modulation access probes is also applicable, and need not be described here.

As shown in FIG. 6, FIG. 6 is a schematic diagram of a network side terminal device transmitting a paging message in Embodiment 1, where the paging message carries an orthogonal code index number, and the terminal device acquires a corresponding according to the orthogonal code index number. An orthogonal code is used, and the orthogonal probe is used to modulate the access probe. Example 2

As shown in FIG. 7, it is a schematic flowchart of Embodiment 2 of the present invention. In this embodiment, the network side can correctly solve the access probe of the terminal device. As can be seen from the figure, the following steps are included:

S710. The access network selects a Walsh code index number, and assembles a paging message.

S720: The access network modifies the state of the Walsh code index number to be occupied;

S730. The access network starts a timer corresponding to the paging message.

S740. The terminal device modulates the access probe according to the orthogonal code corresponding to the Walsh code index number, and sends an access request to the access network.

S750. The access network modifies the status of the corresponding Walsh code index number to be idle.

S760. The access network clears and releases the timer corresponding to the Walsh code index number.

Example 3

In the embodiment 3 of the present invention, if the network side does not receive the access probe sent by the terminal device before the timer expires, the Walsh code index number may be forcibly released. As shown in FIG. 8, it is a schematic flowchart of Embodiment 3 of the present invention. In this embodiment, the network side does not receive the access probe sent by the terminal device after the expiration of the timer. As can be seen from the figure, the following steps are included:

S810. The access network selects a Walsh code index number, and assembles a paging message.

S820. The access network modifies the state of the Walsh code code quote to occupy;

S830. The access network starts a timer corresponding to the paging message.

S840. The access network times out does not receive the access probe sent by the terminal device.

S850: The access network modifies the status of the corresponding Walsh code index number to be idle;

S860. The access network clears and releases the timer corresponding to the Walsh code index number.

Example 4

As shown in FIG. 9, it is a schematic diagram of a terminal device access system according to Embodiment 4 of the present invention. As can be seen from the figure, the system includes a network side for accessing the terminal 910.

The network side is configured with:

The orthogonal code information setting unit 920 is configured to send a paging message to the terminal on the network side, and set the finger The orthogonal code information used by the terminal device is shown.

The orthogonal code information maintenance unit 930 is configured to maintain the orthogonal code information.

The timer unit 940 is configured to set a time threshold after the terminal is instructed to use the orthogonal code.

In the solution of the embodiment of the present invention, when the terminal device responds to the paging, the orthogonal code used by the terminal device is allocated by the network side, and is different from the orthogonal code used by other terminal devices that respond to the paging, and is also associated with other terminal devices that initiate the initial call. Different orthogonal codes are used to ensure that the orthogonal codes used by the terminal devices that respond to the paging must not collide with the orthogonal codes used by other terminal devices. Compared with the prior art, the same avoidance is used at the same time. The orthogonal code causes a collision, which can effectively shorten the delay in responding to the paging.

Since the orthogonal codes used by the terminal devices responding to the paging must not collide, the random backoff time designed to avoid collisions in the random access mechanism can be set to 0, so that the delay in responding to the paging can be further shortened. .

In the solution of the embodiment of the present invention, the resources allocated to the terminal device responding to the paging are only a small part of the total available resources (for example, when 64 Walsh codes are used, the proportion is 64/1006=6.36). %), but effectively avoids the collision probability between the paging device and the originating terminal device, and thus indirectly improves the random access performance of the originating terminal device.

It is apparent that those skilled in the art can make various modifications and variations to the invention without departing from the spirit and scope of the invention. Thus, it is intended that the present invention cover the modifications and variations of the inventions

Claims

Rights request

A method for accessing a terminal device, comprising:

And acquiring, by the terminal device, the corresponding orthogonal code according to the orthogonal code information, and modulating the access probe according to the orthogonal code;

2. The method of claim 1 wherein:

The network side sends a paging message to the terminal device, where the paging message carries the orthogonal code information indicating the use of the terminal device, where the orthogonal code information is an orthogonal code index;

The terminal device modulates an access probe according to the orthogonal code, and the terminal device acquires a corresponding orthogonal code according to the orthogonal code index and modulates an access probe.

The method of claim 1, wherein the network side sends a paging message to the terminal device, where the paging message carries the orthogonal code information used by the terminal device, where the step is The cross code information is an orthogonal code.

The method according to claim 1, 2 or 3, further comprising: setting a first orthogonal code resource, wherein the network side sends a paging message to the terminal device, where the paging message carries In the step of indicating the orthogonal code information used by the terminal device, the orthogonal code is selected from the first orthogonal code resource, and is used for the terminal device to use.

The method of claim 4, wherein the network side sends a paging message to the terminal device, where the paging message carries the indication that the orthogonal code information used by the terminal device is in the step, the indication The orthogonal code used by the terminal device is different from the orthogonal code currently being used.

The method according to claim 5, wherein the network side sends a paging message to the terminal device, where the paging message carries the step of indicating orthogonal code information used by the terminal device, and further includes a network The first timer is started, and the orthogonal code indicated to the terminal device is set to be unavailable. Status.

7. The method according to claim 6, further comprising the steps of:

The network side cancels the unavailable state of the orthogonal code information used for the terminal device according to the interpretation value set by the first timer.

8. The method of claim 1, 2 or 3, characterized in that

The network side sends a paging message to the terminal device, where the paging message carries the orthogonal code information used by the terminal device, and the network side adds a field in the paging message to indicate that the terminal device is available. Cross code information.

A terminal device accessing system, comprising: a network side for accessing a terminal, wherein the network side is configured with:

The system according to claim 9, wherein the network side is further provided with: an orthogonal code information maintenance unit, configured to maintain the orthogonal code information.

The system according to claim 10, wherein the network side is further configured with: a timer unit, configured to set a time threshold after the terminal device is instructed to use the orthogonal code.