WO2018035851A1

WO2018035851A1 - Communication method and terminal

Info

Publication number: WO2018035851A1
Application number: PCT/CN2016/096930
Authority: WO
Inventors: 沈丽; 刘佳迪; 周君; 封鹏飞; 刘继武
Original assignee: 华为技术有限公司
Priority date: 2016-08-26
Filing date: 2016-08-26
Publication date: 2018-03-01
Also published as: CN108605202A; CN108605202B

Abstract

The present application discloses a communication method and a terminal. The method comprises: determining a moving speed of the terminal; and determining a calibration coefficient of a communication parameter of the terminal according to the moving speed. Thus, the terminal can calibrate the communication parameter in time after adjusting the calibration coefficient of the communication parameter, which can match offset quick change of the communication parameter of a highspeed moving terminal, so as to improve communication performance.

Description

Communication method and terminal

Technical field

The present application relates to the field of communications, and in particular, to a communication method and a terminal.

Background technique

With the development of communication technologies, there is an increasing demand for mobile office use by terminals, and therefore, the requirements for service performance of high-speed mobile terminal communication are also increasing.

However, based on historical and empirical data, if the terminal still uses the communication strategy at rest when moving fast, the communication performance of the terminal may be degraded, such as the deterioration of communication quality.

Summary of the invention

The present application provides a communication method and a terminal, and aims to solve the technical problem that communication performance is reduced when a terminal in high-speed mobile performs data communication.

A first aspect of the present application provides a communication method including the steps of: determining, by a terminal, a rate of movement of the terminal; determining a calibration coefficient of the communication parameter of the terminal according to the rate of movement. It can be seen that after determining the calibration coefficient of the communication parameter based on the moving rate, the communication is performed with the calibrated communication parameters, thereby reducing or avoiding various communication deviations and improving communication performance.

A second aspect of the present application provides a terminal, including: a memory and a processor that store an application and an application to generate data generated by the processor, and the processor executes the application to determine a moving speed of the terminal, and A calibration coefficient of the communication parameter of the terminal is determined according to the moving rate. It can be seen that after determining the calibration coefficient of the communication parameter based on the movement rate, the terminal communicates with the calibrated communication parameters, reduces or minimizes various communication deviations, and improves communication performance.

In an implementation manner, the determining, by the terminal, the calibration parameter of the communication parameter of the terminal according to the moving rate, includes: if the moving rate of the terminal is greater than or equal to the first threshold, using the first calibration coefficient, performing the channel carrier signal frequency received by the terminal Calibrating; if the moving rate of the terminal is less than the first threshold and greater than or equal to a second threshold that is less than the first threshold, using a preset second calibration coefficient, calibrating the frequency of the channel carrier signal received by the terminal; If the moving rate is less than the second threshold, the received third letter is used to receive the letter to the terminal. The channel carrier signal frequency is calibrated. Thereby, the terminal determines the calibration parameter of the channel carrier signal frequency of the terminal based on the moving rate, and demodulates the communication signal carried by the channel carrier signal by using the calibrated channel carrier signal frequency, and adopts a comparison when the moving rate is low. A small calibration coefficient, which in turn reduces the frequency offset adjustment jitter, and when the moving rate is high, a larger calibration coefficient is used to speed up the frequency tracking rate to match the fast change of the fast moving frequency offset, thereby improving the communication performance. .

In an implementation manner, the terminal determines, according to the moving rate, a calibration coefficient of the communication parameter of the terminal, specifically, if the moving rate of the terminal is greater than or equal to the first threshold, using a preset first interpolation factor set to estimate the channel of the terminal. The value is calibrated; if the moving rate of the terminal is less than the first threshold and greater than or equal to the second threshold less than the first threshold, the channel estimation value of the terminal is calibrated using a preset second interpolation factor set; When the moving rate is less than the second threshold, the channel estimation value of the terminal is calibrated using a preset third interpolation factor set. Thereby, the terminal determines the calibration coefficient of the channel estimation value of the terminal based on the moving rate, that is, calibrates the channel estimation value in the different interpolation factor set pairs based on the moving rate, and determines the channel by using the calibrated channel estimation value, and further The communication signal carried by the carrier signal in the channel is demodulated to match the rapid change of the channel deviation without the moving rate, and the communication performance is better improved.

In an implementation manner, after determining the mobility rate of the terminal, the terminal is further configured to: adjust a parameter of the terminal selection network based on the mobility rate, so that the terminal selects a target network that performs communication based on the adjusted parameter, and the base station and the terminal of the target network. The distance is the smallest and the distance decreases as the terminal moves. Thereby, the terminal determines to communicate based on the moving rate to the target network that is closest to the moving direction, and the communication performance is better improved.

DRAWINGS

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings to be used in the embodiments or the prior art description will be briefly described below. Obviously, the drawings in the following description are only It is a certain embodiment of the present application, and other drawings can be obtained according to the drawings without any creative work for those skilled in the art.

1 is a schematic diagram of communication between a terminal and a base station;

FIG. 2 and FIG. 3 are respectively a flowchart of a communication method according to an embodiment of the present invention;

Figure 4 is a diagram showing an example of an embodiment of the present invention;

FIG. 5 is another flowchart of a communication method according to an embodiment of the present invention;

Figure 6 is another exemplary diagram of an embodiment of the present invention;

FIG. 7 is a schematic structural diagram of a terminal according to an embodiment of the present invention.

detailed description

1 is a schematic diagram of communication between a terminal and a base station. For example, when a terminal on a railway moving at high speed communicates with a base station, in a cell service network where the terminal is located, the terminal and the base station pass through the channel. The carrier signal transmits a data signal.

When the terminal is moving fast, the carrier signal in the channel may also have a Doppler frequency deviation, or the estimated value of the channel where the carrier signal is located may also be deviated. These deviations may cause a phenomenon of dropping the network and affect the communication performance of the terminal. .

Among them, the Doppler effect means that when the wave moves toward the observer, the observer's receiving frequency becomes higher, and when the wave source is far away from the observer, the observer's receiving frequency becomes lower. Thus, when the terminal moves relative to the base station, the frequency and/or channel estimation value of the channel carrier signal received by the terminal may deviate. It is assumed that the wavelength of the channel carrier signal between the base station and the terminal is λ, the wave speed is c, and the moving rate of the terminal is v. When the terminal moves near the base station, the frequency of the channel carrier signal is (c+v)/λ, and the terminal is When moving away from the base station, the frequency of the channel carrier signal is (cv) / λ, and correspondingly, similar deviations occur in the channel estimation values.

FIG. 2 is a flowchart of an implementation of a communication method according to an embodiment of the present invention, which is used to solve the problem of communication performance degradation when a high-speed mobile terminal performs communication, and FIG. 2 is a communication of a terminal on a high-speed rail. For example, the terminal solves the above problem by performing the following steps:

S201: Collect a highspeed flag in the system message.

The system message here refers to the message in the network where the terminal is located, and the highspeed flag can indicate whether the cell network where the terminal is located supports the selection of the ZC (Zadoff-Chu) sequence cyclic shift in the high-speed mobile, thereby indicating whether the terminal is in the high-speed rail network. Medium, that is, whether the terminal is in the riding state.

S202: Determine the value of the highspeed flag. If the value of the highspeed flag is true, it indicates that the terminal is in a high-speed moving state, and S203 to S204 are executed. If the value of the highspeed flag is false, the terminal may be in a non-high-speed moving state, and S205 is executed.

S203: Obtain sensing parameters of each sensor through a sensor hub.

Among them, the sensors here can be: acceleration sensors, gyroscopes and barometers. The corresponding sensing parameters can include parameters such as acceleration, inclination and air pressure.

S204: Obtain a moving rate of the terminal based on the obtained sensing parameter in step S203, and determine whether the moving rate of the terminal exceeds a preset first threshold.

The sensing parameter includes sensing parameters obtained by each sensor, and the moving speed of the terminal is obtained based on the at least one sensing parameter.

S205: It is judged by the sensor hub whether the terminal is in the riding state, and if the terminal is in the riding state, S206 is performed.

In this embodiment, the sensor hub determines whether the terminal is in the riding state by integrating the sensing parameters of the respective sensors and using a general algorithm such as a classifier or a decision tree in combination with a specific implementation.

S206: Acquire a moving rate of the terminal by using a GPS (Global Positioning System) in the terminal, and execute S207.

In this embodiment, before the mobile terminal obtains the moving rate of the terminal, the sensor hub is used to determine whether the terminal is in the riding state, and the GPS is turned on only when the terminal is in the riding state, and the moving speed of the terminal is acquired by using the GPS. When the terminal is not in the riding state, it is not necessary to trigger the GPS to acquire the moving rate, thereby avoiding unnecessary resource consumption.

S207: Determine whether the moving rate is greater than or equal to the first threshold.

The above first threshold can be set according to requirements, such as 200 km/h (km/h).

The purpose of the above S201 to S207 is to obtain the moving rate of the terminal, and determine whether the moving rate of the terminal exceeds the first threshold.

When it is determined in S204 that the moving rate of the terminal exceeds (greater than or equal to) the first threshold, or when it is determined in S207 that the moving rate exceeds the first threshold, the frequency of the channel carrier signal received by the terminal may be deviated, if not Timely adjustment or calibration, there will be a channel carrier signal The communication signal with the band cannot be demodulated, causing the phenomenon of dropping the network or interrupting the service.

In this embodiment, the terminal may calibrate the frequency of the carrier signal in the channel based on the real-time rate to avoid the situation that the terminal is disconnected from the network or the terminal service. Specifically, the terminal performs the S208 to S211 to implement the frequency of the carrier signal in the channel. Calibration, as shown in FIG. 2, if the movement rate exceeds the first threshold, S208 is performed, and if the movement rate does not exceed the first threshold, S209 is performed:

S208: Calibrate the received channel carrier signal frequency by using a preset first calibration coefficient.

S209: determining whether the moving rate is greater than or equal to a preset second threshold and less than the first threshold, the second threshold is less than the first threshold, and the second threshold may be 100 km/h or 80 km/h, if the moving rate exceeds the second threshold, Execution S210, if the movement rate is less than the second threshold, S211 is performed.

S210: Calibrate the received channel carrier signal frequency by using a preset second calibration coefficient.

S211: Calibrate the received channel carrier signal frequency by using a preset third calibration coefficient.

Here, the values of the first calibration coefficient, the second calibration coefficient and the third calibration coefficient are between 0 and 1, and the first calibration coefficient is greater than the second calibration coefficient, and the second calibration coefficient is greater than the third calibration coefficient.

In the embodiment, when the calibration channel coefficient is used to calibrate the received channel carrier signal frequency, the following formula (1) can be specifically implemented:

F1=f2+a×△f (1)

among them:

F1 is the frequency of the channel carrier signal after calibration.

F2 is the frequency of the channel carrier signal received by the terminal.

△f is the calibration frequency. In the specific implementation, Δf can be positive or negative.

Among them, based on the related content of the Doppler effect in the foregoing, the positive and negative values of Δf depend on the relative operation between the terminal and the base station. For example, when the terminal moves close to the base station, Δf takes a positive value, and when the terminal moves away from the base station, Δf takes a negative value.

The value of Δf is based on the relevant content of the Doppler effect in the previous context, depending on the terminal relative The ratio between the rate of movement v of the base station and the rate of propagation of the signal in the medium (air).

a is a calibration coefficient, and the value of a is different based on the moving rate of the terminal. For example, when the moving rate of the terminal is greater than the first threshold, a takes the value a1 (the terminal is on the high-speed running high-speed rail), and the moving speed of the terminal is smaller than the first When a threshold is greater than the second threshold, a takes the value a2 (the terminal is on a high-speed vehicle such as a bus), and when the moving rate of the terminal is less than the second threshold, a takes the value a3 (the terminal is in a stationary or walking state), A1 is greater than a2, and a2 is greater than a3.

Therefore, the terminal demodulates the communication signal carried by the channel carrier signal by using the calibrated channel carrier signal frequency, for example, using a robust frequency calibration scheme in a non-high-speed rail scenario, such as using a smaller calibration coefficient to reduce the frequency offset. Adjust the jitter, and use the fast tracking frequency offset adjustment scheme in the high-speed rail scenario, such as using a larger calibration coefficient to speed up the frequency tracking rate to match the rapid change of the frequency offset in the high-speed rail scene, thereby improving the communication performance.

When it is determined in S204 that the moving rate of the terminal exceeds the first threshold, or when it is determined in S207 that the moving rate exceeds the first threshold, the channel estimation value of the carrier signal received by the terminal may be biased, if not timely Adjustment or calibration may result in the situation that the communication signal carried by the carrier signal cannot be demodulated, causing the network to be dropped or the service to be interrupted.

In this embodiment, the terminal performs calibration of the channel estimation value of the terminal by performing S212 to S215. As shown in FIG. 3, if the moving rate is greater than or equal to (exceeds) the first threshold, S212 is performed, if the moving rate is not Exceeding the first threshold, executing S213:

S212: Calibrate the channel estimation value by using a preset first interpolation factor set.

S213: Determine whether the moving rate is greater than or equal to (above) the preset second threshold and is less than the first threshold, the second threshold is less than the first threshold, if the moving rate exceeds the second threshold, perform S214, if the moving rate is less than the second threshold , execute S215.

S214: Calibrate the channel estimation value by using a preset second interpolation factor set.

S215: Calibrate the channel estimation value by using a preset third interpolation factor set.

Here, the first set of interpolation factors, the second set of interpolation factors are different from the interpolation factors in the third interpolation factor, and the values of these interpolation factors are between 0 and 1, and are adjustable.

In this embodiment, the frequency domain response value at the pilot channel may be first estimated by using the pilot, and then the channel estimation value at the non-pilot carrier is obtained by using an interpolation scheme, for example, using the following formula (2) to implement the non-pilot output. The channel estimate of the carrier is calibrated:

H(m,l)=b1×H(m-1,l)+b2×H(m+1,l)+b3×H(m,l-1)+b4×H(m,l+1) (2)

among them:

m in H(m,l) is the row identifier, l is the column identifier, and H(m,l) is the channel estimation value of the pilot in the mth row and the first column, H(m-1,l), Channel estimation of adjacent four non-pilot carrier signals of H(m+1,l), H(m,l-1) and H(m,l+1) respectively H(m,l) The value is a lattice adjacent to the circumference (up, down, left, and right) centered on H(m, l) as shown in FIG.

B1 to b4 are interpolation factors respectively. The values of b1 to b4 are different depending on the moving rate of the terminal. For example, when the moving rate of the terminal is greater than the first threshold, if the terminal is on a high-speed high-speed rail, b1 to b4 may The values are: 0.3, 0.3, 0.7, and 0.7; when the moving rate of the terminal is less than the first threshold but greater than the second threshold, if the terminal is in a high-speed running vehicle such as a bus, b1 to b4 may have a value of 0.5. 0.5, 0.5, and 0.5; when the moving rate of the terminal is less than the second threshold, if the terminal is in a stationary or walking state, b1 to b4 may take values of 0.7, 0.7, 0.3, and 0.3.

Therefore, the terminal determines the channel with the calibrated channel estimation value, and demodulates the communication signal carried by the carrier signal in the channel to match the rapid change of the channel deviation in the high-speed rail scenario, thereby improving the communication performance.

In addition, when it is determined in S204 that the vehicle in which the terminal is located has a moving rate exceeding a first threshold, or when it is determined in S207 that the moving rate exceeds the first threshold, the terminal may also have a lower efficiency of selecting a network policy, causing a dropped network or interrupted service. phenomenon.

In this embodiment, the terminal optimizes the network selection policy of the terminal by performing S216 to S217. As shown in FIG. 5, if the moving rate exceeds the first threshold, S216 is performed:

S216: Determine each cell network where the terminal is located.

S217: In each cell network, adjusting parameters of the terminal selection network, so that the terminal selects a target network for communication based on the adjusted parameters of the network selection, the distance between the base station and the terminal of the target network is the smallest, and the distance decreases with the movement of the terminal. That is, the direction of movement of the terminal is toward the base station of the target network.

Wherein, the parameter of the terminal selection network may be a weight parameter or a hysteresis parameter of a communication parameter such as a signal strength, and the adjusted weight parameter or the hysteresis parameter is used to change the network selection strategy, and the network reselection is frequently performed to determine the distance terminal. The communication network of the base station that is closest to the direction of movement of the terminal is the target network.

As shown in FIG. 6, the terminal has four cell networks A, B, C, and D, and the moving direction of the terminal is as shown in the figure. Therefore, it is determined that the cell network C is the target network, and the terminal passes the nearest distance and is coming. The closer the cell network performs data communication, thereby improving communication performance.

It should be noted that, in the foregoing solutions for improving communication quality: S208-S211, S212-S215, and S216-S217, may be performed simultaneously, or may be selected according to current needs of the terminal, such as the remaining amount of power or the current state of the terminal. One or two of these solutions improve communication quality. For example, the schemes of S208 to S211 and S212 to S215 can be applied to terminals in a communication connection state, such as terminals that are performing voice communication or short message transmission; and S216 to S217 can be applied to terminals that do not perform any data transmission.

FIG. 7 is a schematic structural diagram of a terminal in FIG. 1, and the terminal in FIG. 7 may include the following structure:

The bus 701 is used to connect various components in the terminal.

The communication interface 702 and the antenna 703 are connected to the bus 701 via the communication interface 702.

Modem 704 is coupled to bus 701.

The memory 705 is connected to the bus 701 for storing data generated by applications and application operations.

The processor 706 is configured to execute an application, determine a moving rate of the terminal, and determine a calibration coefficient of the communication parameter of the terminal according to the moving rate, whereby the communication parameter of the terminal is adjusted according to the determined calibration coefficient, and then the modem 704 Communication is performed through the antenna 703 using the adjusted communication parameters.

An implementation structure of the terminal is shown in FIG. 7. The implementation functions of each structure in the terminal may be implemented in the foregoing, and are not described in detail herein.

The various embodiments in the specification are described in a progressive manner, and each embodiment focuses on differences from other embodiments, and the same or similar parts of the respective embodiments may be referred to each other.

Claims

A communication method is characterized in that it is applied to a terminal, and the method includes:

Determining, by the terminal, a moving rate of the terminal;

A calibration coefficient of the communication parameter of the terminal is determined according to the moving rate.
The method of claim 1 wherein said communication parameters comprise: a channel carrier signal frequency of said terminal.
The method according to claim 2, wherein determining a calibration coefficient of the communication parameter of the terminal according to the moving rate comprises:

If the moving rate of the terminal is greater than or equal to the first threshold, using a preset first calibration coefficient, calibrating the frequency of the channel carrier signal received by the terminal;

If the moving rate of the terminal is less than the first threshold and greater than or equal to the second threshold, the frequency of the channel carrier signal received by the terminal is calibrated using a preset second calibration coefficient;

If the moving rate of the terminal is less than the second threshold, calibrating the frequency of the channel carrier signal received by the terminal by using a preset third calibration coefficient,

The first threshold is greater than the second threshold.
The method of claim 1 wherein said communication parameters comprise: channel estimate values of said terminal.
The method according to claim 4, wherein determining a calibration coefficient of the communication parameter of the terminal according to the moving rate comprises:

If the moving rate of the terminal is greater than or equal to the first threshold, calibrating the channel estimation value of the terminal by using a preset first interpolation factor set;

If the moving rate of the terminal is less than the first threshold and greater than or equal to the second threshold, the channel estimation value of the terminal is calibrated using a preset second interpolation factor set;

If the moving rate of the terminal is less than the second threshold, calibrating the channel estimation value of the terminal by using a preset third interpolation factor set;

The first threshold is greater than the second threshold.
The method according to claim 1, wherein the communication parameter of the terminal comprises: a parameter of a terminal selection network.
The method according to claim 6, wherein after determining the moving rate of the terminal, the method further comprises:

And adjusting, according to the moving rate, a parameter of the terminal selection network, so that the terminal selects a target network that performs communication based on the adjusted parameter, a distance between a base station of the target network and the terminal is the smallest, and the distance is As the movement of the terminal decreases.
A terminal, comprising: a memory and a processor, wherein:

The memory is configured to store data generated by an application and an application running;

The processor is configured to execute the application to implement a function of determining a moving rate of the terminal, and determining a calibration coefficient of a communication parameter of the terminal according to the moving rate.
The terminal according to claim 8, wherein the processor determines a calibration coefficient of the communication parameter of the terminal according to the moving rate, specifically:

If the moving rate of the terminal is greater than or equal to a preset first threshold, the processor uses a preset first calibration coefficient to calibrate the frequency of the channel carrier signal received by the terminal;

If the moving rate of the terminal is less than the first threshold and greater than or equal to a preset second threshold, the processor performs a channel carrier signal frequency received by the terminal by using a preset second calibration coefficient. calibration;

If the moving rate of the terminal is less than the second threshold, the processor calibrates the frequency of the channel carrier signal received by the terminal by using a preset third calibration coefficient,

The first threshold is greater than the second threshold.
The terminal according to claim 8, wherein the processor determines a calibration coefficient of the communication parameter of the terminal according to the moving rate, specifically:

If the moving rate of the terminal is greater than or equal to a preset first threshold, using a preset first interpolation factor set, calibrating the channel estimation value of the terminal;

If the moving rate of the terminal is less than the first threshold and greater than or equal to a preset second threshold, the channel estimation value of the terminal is calibrated using a preset second interpolation factor set;

If the moving rate of the terminal is less than the second threshold, calibrating the channel estimation value of the terminal by using a preset third interpolation factor set;

The first threshold is greater than the second threshold.
The terminal according to claim 8, wherein after determining the moving rate of the terminal, the processor is further configured to:

Adjusting, according to the moving rate, a parameter of the terminal selection network, so that the terminal selects a target network that performs communication based on the adjusted parameter, where a distance between a base station and a terminal of the target network is the smallest, and the distance is The movement of the terminal is reduced.