WO2013104212A1

WO2013104212A1 - Random access detection method and device

Info

Publication number: WO2013104212A1
Application number: PCT/CN2012/084958
Authority: WO
Inventors: 汪玲; 蒋一鸣
Original assignee: 大唐移动通信设备有限公司
Priority date: 2012-01-09
Filing date: 2012-11-21
Publication date: 2013-07-18
Also published as: CN102547831A

Abstract

Disclosed are a random access detection method and device, which relate to communication technology. The method comprises: determining a received signal power through a peak power and a power value of a sampling point close to a peak position; judging whether a preamble sequence exists in a detection window through the received signal power, instead of judging whether a preamble sequence exists in a detection window only through the power value of one sampling point. The problem of detection performance reduction caused by peak power dispersion which is generated due to time delay is solved.

Description

The present invention claims the priority of a Chinese patent application filed on January 9, 2011 by the Chinese Patent Office, the application number is 201210004784.6, and the invention is entitled "a random access method and device". The entire contents of this application are incorporated herein by reference. Technical field

The present invention relates to communication technologies, and in particular, to a random access method and apparatus. Background technique

At present, in a communication system such as Long Term Evolution (LTE), a user equipment (UE) establishes uplink synchronization through a random access and a base station (eNodeB) and requests the eNodeB to allocate dedicated resources for uplink transmission, thereby performing normal operation. Business transmission.

After the UE is powered on, the downlink time frequency synchronization process and the cell identity (ID) detection are performed. If a suitable cell is found, it resides in the cell, and the system broadcast information of the cell is interpreted, and then enters the idle state (RRC_IDLE). In the idle state, the UE will listen to its own paging message and whether the system message of the camping cell changes, update the content of the system message in time, and maintain the real-time downlink synchronization state of the cell.

Although the UE and the eNodeB always maintain the downlink synchronization relationship, since the start time of the eNodeB downlink transmission frame is unknown, the distance between the UE and the eNodeB is uncertain. If the UE needs to send a message to the eNodeB or the eNodeB, it needs to send a message to the UE. Then, the random access process must be established to establish uplink synchronization, and the uplink synchronization needs to be maintained in real time until the process is completed.

The process of the UE communicating with the eNodeB is as shown in FIG. 1 and includes:

Step S101: The eNodeB performs cell search, establishes downlink synchronization, and obtains system information.

Step S102: The UE establishes a random access procedure with the eNodeB, completes uplink synchronization, and requests resources.

Step S103: The UE communicates with the eNodeB.

At this time, the role of random access has two aspects. One is that the base station identifies the preamble ID sent by the user to allocate resources for the user, and the other is to complete the uplink synchronization process.

At present, the algorithm for performing random access detection is to determine whether there is sequence access according to the ratio of the peak value of the related preamble (Preamble) sequence and the noise power in a detection window. The specific processing flow is as shown in FIG. 2, including:

Step S201, calculating peak power and peak position in the detected detection window;

Step S202: Calculate a noise power W in the detection window. ;

Step S203, determining whether there is Preamble sequence access in the detection window, if there is sequence access, performing step S204, if there is no sequence access, performing step S206; when detecting whether there is Preamble sequence access, It is judged whether the signal-to-noise ratio is greater than the set threshold. If ≥ V _{detecl ArMd} * N , it is determined that there is sequence access, otherwise it is determined that there is no sequence access, where C. 'To receive the signal power, ^Ρ ' ⁼ Ρ ^ΚΛ^Μ is the detection threshold, which is related to the number of receiving antennas and the parameter configuration of the Preamble sequence.

Step S204: Calculate a timing adjustment amount of the Preamble sequence corresponding to the detection window according to the peak power position; Step S205: Find a timing adjustment command word of the corresponding Preamble sequence;

Step S206: Report the detection result of the random access to the upper layer.

It can be seen from step S203 that when it is determined whether there is sequence access, whether the ratio of the received signal power to the noise power exceeds the threshold value is determined. If the threshold is exceeded, the sequence access is indicated, otherwise there is no sequence access. At this time, the received signal power is equal to the peak power in the detection window.

When it is extended to an integral multiple of the Preamble sequence sample point, the correlated energy is concentrated at one sample point. As shown in Fig. 3a, only one peak appears at the position 130. When the delay is not ideal, the correlation is The energy is not concentrated at one sample point, but is diffused to thousands of sample points, thus reducing the signal power of a sample point, thereby reducing the performance of the detection, as shown in Figure 3b. The energy is dispersed to the positions 130 and 131 respectively. When the random access detection is performed by the signal-to-noise ratio, the peak power may be dispersed due to the delay, and the detection performance is degraded. Summary of the invention

Embodiments of the present invention provide a random access detection method and apparatus to solve the problem of degradation of detection performance caused by peak power dispersion caused by delay.

A random access detection method includes:

Determining peak power and peak position within the detection window;

Determining a power value of the peak position adjacent to the sample point, and determining a received signal power according to the power value of the peak position adjacent to the sample point and the peak power, wherein the peak position is adjacent to the sample point: Set the number of sample points and/or the number of points on the right side of the peak position;

Determining whether there is a Preamble sequence in the detection window according to the received signal power, and reporting the detection result to the upper layer.

A random access detecting device includes:

a peak determining unit, configured to determine a peak power and a peak position in the detection window;

a power determining unit, configured to determine a power value of the peak position adjacent to the sample point, and determine a received signal power according to the power value of the peak position adjacent to the sample point and the peak power, where the peak position is adjacent to the sample point To: set the number of sample points on the left side of the peak position and/or set the number of sample points on the right side of the peak position;

And a detecting unit, configured to determine, according to the received signal power, whether there is a Preamble sequence in the detection window, and perform a detection result on a high layer. The embodiment of the invention provides a random access detection method and device, which determines the received signal power by the peak power and the power value of the peak position adjacent to the sample point, and determines whether there is a Preamble sequence in the detection window by using the received signal power. It is not only judged whether there is a Preamble sequence in the detection window by the power value of one sample point, and the problem that the detection performance is degraded due to the peak power dispersion due to the delay is solved. DRAWINGS

1 is a schematic diagram of application of a random access procedure in the prior art;

2 is a flow chart of a random access detection method in the prior art;

3a and 3b are schematic diagrams of power distribution in the prior art;

4 is a flowchart of a random access detection method according to an embodiment of the present invention;

FIG. 5 is a flowchart of a preferred random access detection method according to an embodiment of the present invention;

FIG. 6 is a schematic structural diagram of a random access detecting apparatus according to an embodiment of the present invention. detailed description

The embodiment of the invention provides a random access detection method and device, which determines the received signal power by the peak power and the power value of the peak position adjacent to the sample point, and determines whether there is a Preamble sequence in the detection window by using the received signal power. It is not only judged whether there is a Preamble sequence in the detection window by the power value of one sample point, and the problem that the detection performance is degraded due to the peak power dispersion due to the delay is solved.

As shown in FIG. 4, the random access detection method provided by the embodiment of the present invention includes:

Step S401, determining peak power and peak position in the detection window;

Step S402, determining the power value of the peak position adjacent to the sample point, and determining the received signal power according to the power value and the peak power of the peak position adjacent to the peak position, and the peak position is adjacent to the sample point: Number of sample points and/or peak positions to the right of the peak position;

Step S403: Determine whether there is a Preamble sequence in the detection window according to the received signal power, and report the detection result to the upper layer.

In step S402, the received signal power is determined according to the power value of the peak position and the peak power, and the power values of the plurality of sample points and the peak power are generally summed to determine the received signal power. The number of power values near the peak position of the peak position needs to be appropriate. When the peak position is close to the number of power points of the sample point, the detection threshold may increase, which is not conducive to the improvement of detection performance. Generally, the number of power values of the peak position adjacent to the sample point is less than 4, and it is better when the peak position is less than two.

Further, in order to prevent the peak position from being too close to the power value of the sample point, a maximum power value other than the peak power and the peak power may be selected to obtain the received signal power. At this time, in step S402, the peak position is determined. Pro The power value of the sample point is near, and the power of the received signal is determined according to the power value of the peak position and the peak power, and the specificity includes:

Determining the maximum power value of the power value of the peak position adjacent to the sample point;

The received signal power is determined to be the sum of the peak power and the maximum power value.

In order to prevent the maximum power value from being introduced into the received signal power to affect the detection result when peak power dispersion does not occur, the peak power may be further determined after determining the maximum power value of the power value of the peak position adjacent to the sample point. And a ratio of the maximum power value, when the ratio is greater than a preset threshold, determining that the received signal power is the peak power, otherwise determining that the received signal power is the peak power and the maximum power The sum of the values.

In general, the maximum power value in the power value of the peak position adjacent to the sample point is the adjacent sample point on both sides of the peak position, so when determining the peak value of the maximum power value in the power value of the sample point, The left peak power and the right peak power can be directly compared to determine a larger one as the maximum power value of the power value of the peak position adjacent to the sample point, wherein the left peak power and the right peak power are respectively the peak position The power value of the adjacent sample.

When determining the left peak power and the right peak power, the following rules can be followed:

When the peak position TA _max =0, it is determined that the left peak power is 0, and the right peak power is determined as the power value of the TA _max +l position;

When the peak position TA _max = N _cs, the left peak power is determined power value TA _max -l position, determining the right peak power 0, N _cs is the window length of the detection window;

TA _max When the peak position is other values, to determine the peak power value of power left TA _max -l position, the right to determine the peak power of the power value TA _max + l position.

Determining whether there is a Preamble sequence in the detection window according to the received signal power includes:

When the ratio of the received signal power to the noise power in the detection window is greater than a preset threshold, it is determined that there is a Preamble sequence in the detection window. Otherwise, it is determined that there is no Preamble sequence in the detection window. When the Preamble sequence is determined in the detection window, the Determine the timing adjustment amount and timing adjustment command word.

Specifically, a preferred random access detection method is shown in FIG. 5, including:

Step S501, calculating peak power and peak position in the detected detection window;

Step S502, calculating noise power in the detection window;

Step S503, determining left peak power and right peak power; when the peak position TA _max =0, determining that the left peak power is 0, determining that the right peak power is the power value of the TA _max +l position; when the peak position TA _max = N _cs When determining the left peak power as the power value of the TA _max -l position, determining that the right peak power is 0, N _cs is the window length of the detection window; when the peak position TA _max is other values, determining the left peak power as TA _max The power value of the -l position, determining the power value of the right peak power as the TA _max +l position;

Step S504, determining a left peak power and a right peak power, the larger one being the peak position adjacent to the sample point The maximum power value in the power value;

Step S505, determining a ratio of the peak power to the maximum power value. When the ratio is greater than a preset threshold, determining that the received signal power is the peak power, otherwise determining that the received signal power is Determining the sum of the peak power and the maximum power value;

Step S506, determining whether there is Preamble sequence access in the detection window, if there is sequence access, performing step S507, if there is no sequence access, performing step S509; and detecting whether there is Preamble sequence access, may adopt signal noise Determine whether the ratio is greater than or equal to the set threshold, if ≥ V = * N. , determining sequence access, otherwise determining that there is no sequence access, wherein the received signal power is a detection threshold, and is related to the number of receiving antennas and the parameter configuration of the Preamble sequence;

Step S507: Calculate a timing adjustment amount of the Preamble sequence corresponding to the detection window according to the peak power position; Step S508, and obtain a timing adjustment command word of the corresponding Preamble sequence;

Step S509: Report the detection result of the random access to the upper layer.

The embodiment of the present invention further provides a random access detecting device. As shown in FIG. 6, the device includes: a peak determining unit 601, configured to determine a peak power and a peak position in the detecting window;

The power determining unit 602 is configured to determine a power value of the peak position adjacent to the sample point, and determine a received signal power according to the power value of the peak position adjacent to the sample point and the peak power, where the peak position is adjacent to the sample point: Set the number of sample points on the left side of the position and/or set the number of sample points on the right side of the peak position;

The detecting unit 603 is configured to determine whether there is a Preamble sequence in the detection window according to the received signal power, and report the detection result to the upper layer.

The power determining unit 602 is specifically configured to:

Alternatively, the power determining unit 602 is specifically configured to:

The ratio of the peak power to the maximum power value is determined. When the ratio is greater than a preset threshold, the received signal power is determined to be the peak power, otherwise the received signal power is determined to be the sum of the peak power and the maximum power value.

The power determining unit 602 determines a maximum power value of the power value of the peak position adjacent to the sample point, and specifically includes: determining a left peak power and a right peak power, wherein the left peak power and the right peak power are adjacent sampling points on both sides of the peak position, respectively. Power value

The larger of the left peak power and the right peak power is used as the peak value of the maximum power value among the power values of the sample points.

Further, the power determining unit 602 determines the left peak power and the right peak power, and specifically includes: When the peak position TA _max =0, it is determined that the left peak power is 0, and the right peak power is determined as the power value of the TA _max +l position;

Those skilled in the art will appreciate that embodiments of the present invention can be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or a combination of software and hardware. Moreover, the present invention can be embodied in the form of a computer program product embodied on one or more computer-usable storage interfaces (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer usable program code.

The present invention has been described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block of the flowchart illustrations and/or FIG. These computer program instructions can be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing device to produce a machine for the execution of instructions for execution by a processor of a computer or other programmable data processing device. Means for implementing the functions specified in one or more of the flow or in a block or blocks of the flow chart.

The computer program instructions can also be stored in a computer readable memory that can direct a computer or other programmable data processing device to operate in a particular manner, such that the instructions stored in the computer readable memory produce an article of manufacture comprising the instruction device. The apparatus implements the functions specified in one or more blocks of a flow or a flow and/or block diagram of the flowchart.

These computer program instructions can also be loaded onto a computer or other programmable data processing device such that a series of operational steps are performed on a computer or other programmable device to produce computer-implemented processing for execution on a computer or other programmable device. The instructions provide steps for implementing the functions specified in one or more of the flow or in a block or blocks of a flow diagram.

Although the preferred embodiment of the invention has been described, it will be apparent to those skilled in the art that, Therefore, the appended claims are intended to be construed as including the preferred The embodiments and all changes and modifications that fall within the scope of the invention.

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 the modifications of the invention

Claims

Rights request

A random access detection method, comprising:

Determining peak power and peak position within the detection window;

Determining whether there is a preamble Preamble sequence in the detection window according to the received signal power, and reporting the detection result to the upper layer.

2. The method according to claim 1, wherein the determining a peak position is adjacent to a power value of the sample point, and determining a received signal according to the power value of the peak position adjacent to the sample point and the peak power. Power, specifically includes:

3. The method according to claim 1, wherein the determining a peak position is adjacent to a power value of the sample point, and determining a received signal according to the power value of the peak position adjacent to the sample point and the peak power. Power, specifically includes:

Determining a ratio of the peak power to the maximum power value, determining that the received signal power is the peak power when the ratio is greater than a preset threshold, and determining that the received signal power is the peak power And the sum of the maximum power values.

The method according to claim 2 or 3, wherein the determining the maximum power value of the power value of the peak position adjacent to the sample point comprises:

Determining a left peak power and a right peak power, wherein the left peak power and the right peak power are respectively power values of adjacent sample points on both sides of the peak position;

The larger of the left peak power and the right peak power is used as the maximum power value of the power value of the peak position adjacent to the sample point.

The method according to claim 4, wherein the determining the left peak power and the right peak power comprises:

When the peak position TA _max = N _cs, the left peak power is determined power value TA _max -l position, the right to determine the peak power of 0, the N _cs window length detection window; TA _max When the peak position is other values, to determine the peak power value of power left TA _max -l position, the right to determine the peak power of the power value TA _max + l position.

6. A random access detecting device, comprising:

And a detecting unit, configured to determine, according to the received signal power, whether there is a Preamble sequence in the detection window, and to detect the result to the upper layer.

The device according to claim 6, wherein the power determining unit is specifically configured to:

The device according to claim 7 or 8, wherein the power determining unit determines a maximum power value of the power value of the peak position adjacent to the sample point, which specifically includes:

The apparatus according to claim 9, wherein the power determining unit determines the left peak power and the right peak power, and specifically includes:

When the peak position TA _max = N _cs, the left peak power is determined power value TA _max -l position, the right to determine the peak power of 0, the N _cs window length detection window;