阅读说明：本技术 一种室内信号跟踪方法 (Indoor signal tracking method ) 是由 彭艺 谢钊萍 于 2021-07-12 设计创作，主要内容包括：本发明公开一种室内信号跟踪方法,属于无线通信网络技术领域。本发明主要利用CW传播模型进行仿真,实现对信号传播路径的跟踪,通过跟踪射线还原信号的真实传播路径。将室内场景分为了两个部分,视距通信场景和非视距通信场景。在室内视距通信场景,沿用传统的室内信号跟踪方法；在非视距室内通信场景,利用通信仿真软件Atoll进行测试场景模拟。本发明与传统的模式矩阵方法相比,CW传播模型利用射线跟踪和测试场景校正过程,可以更好的发现测试场景中的信号盲区,避免实地测试带来的人力物力损耗,提高室内通信质量。(The invention discloses an indoor signal tracking method, and belongs to the technical field of wireless communication networks. The invention mainly utilizes a CW propagation model to simulate, realizes the tracking of the signal propagation path and restores the real propagation path of the signal by tracking rays. The indoor scene is divided into two parts, a line-of-sight communication scene and a non-line-of-sight communication scene. In an indoor line-of-sight communication scene, a traditional indoor signal tracking method is used; and in a non-line-of-sight indoor communication scene, utilizing communication simulation software Atoll to simulate a test scene. Compared with the traditional mode matrix method, the CW propagation model utilizes ray tracing and test scene correction processes, can better find signal blind areas in a test scene, avoids manpower and material resource loss caused by field test, and improves indoor communication quality.)

1. An indoor signal tracking method, comprising the steps of:

s1, analyzing the test scene by combining the indoor condition of the test scene and the peripheral outdoor condition;

s2, setting parameters of the transmitting and receiving antenna and the off-grid analyzer according to the analysis result;

s3, simulating the signal coverage condition in the whole room, wherein when the transmitting point and the receiving point belong to line-of-sight transmission, an LEE model is adopted for simulation, and when the transmitting point and the receiving point belong to non-line-of-sight transmission, a CW model is adopted for simulation;

s4, comparing the simulation result with the standard data, judging whether the simulation result is in the standard range, if not, correcting the model parameters until the simulation result reaches the standard;

and S5, completing indoor signal propagation tracking work and determining a signal propagation scheme.

2. The indoor signal tracking method of claim 1, wherein the indoor conditions in step S1 include identifying wall material, estimating space loss, surveying existing signal coverage, whether the signal is directly available, and identifying whether there is hot spot coverage; the outdoor situation comprises the steps of obtaining the wireless environment situation around the test scene, analyzing the mutual influence of the station and the indoor signal coverage, and checking the position of the antenna point.

3. The indoor signal tracking method of claim 1, wherein the visual distance propagation simulation process in step S3 is:

s31, collecting data according to the set model parameters, placing a receiver at the edge of a receiving point for data recording, and calculating the path loss between a transmitting point and the receiving point through a path loss formula to obtain the receiving power of the LEE model;

s32, analyzing whether the received power is in a standard range, if so, meeting the coverage requirement of indoor line-of-sight transmission, and if not, changing the position and input power of the antenna and continuing to simulate the indoor line-of-sight transmission without meeting the coverage requirement of the indoor line-of-sight transmission;

and S33, repeating the step S32 until the received power reaches a specified range, namely the simulation result is qualified.

4. The indoor signal tracking method of claim 1, wherein the non-line-of-sight propagation simulation process in step S3 is:

s34, setting parameters of the CW model, selecting a sending point and a receiving point to perform ray tracing of the CW model, namely setting a CW propagation environment, performing signal tracing and combining an electromagnetic environment to obtain receiving power;

s35, judging loss according to the received power of the receiving point, comparing the received power with standard data, if the received power meets the standard, successfully tracing the CW model, if the received power does not meet the standard, correcting the CW model according to the test point and the test route map;

and S36, repeating the step S35 until the tracking effect of the CW model reaches the standard, namely finishing the signal propagation tracking work and determining the propagation scheme.

5. The indoor signal tracking method of claim 3, wherein the path loss formula in step S31 is:

wherein d is₁Is the apparent distance of propagation, λ is the wavelength, h_aFor transmitting antenna height, h_mFor receiving the antenna height, alpha_rThe loss of the floor dielectric is B, and the loss caused by other objects in the room is B.

6. The indoor signal tracking method of claim 4, wherein the received power in step S35 is:

converting the path loss to dB, the ratio between transmit and receive power is obtained as:

where K is the number of rays, U is the number of first reflections occurring, V is the number of second reflections occurring, I is the number of diffractions, d is the distance, P_kIs the k-th ray arrival power, R_uIs the gain, R, of the receiving antenna after the u-th occurrence of two reflections_vIs the gain, T, of the receiving antenna after the v-th occurrence of two reflections_iIs the gain of the transmitting antenna after the ith diffraction.

Technical Field

The invention relates to the technical field of wireless communication networks, in particular to an indoor signal tracking method.

Background

At present, people can not leave a network in life, whether in an office building or a living residential area, and people need the network to work, study, live and entertain in indoor environment. According to incomplete statistics, about 60% -70% of mobile communication throughout the country is performed indoors.

However, with the development of urban construction, due to the shielding and absorbing functions of buildings themselves, after the signals are emitted, the signals are easily affected by the reflection, refraction and diffraction phenomena of objects such as indoor walls, sofas, windows and the like, so that the signals are greatly attenuated, and indoor scenes cannot be better covered; on the other hand, in large shopping malls, conference centers and other scenes, local network capacity cannot meet user requirements due to excessive mobile communication density. There are two main types of currently implemented communication coverage schemes: one is through direct coverage by indoor and outdoor base stations; the other is covered by a distribution system, including an outdoor distribution system and an indoor cable optical fiber distribution system, which play a positive role in the early stage of the coverage construction of the mobile communication indoor. However, in the later stage of the indoor coverage construction of the mobile communication network, in order to improve the indoor communication effect of the communication network, if the whole indoor signal coverage can be monitored and observed in real time, there are many advantages, including: and an indoor signal blind area is found, the indoor coverage is improved, and the transmission loss under different environments is analyzed, so that a better indoor communication system is obtained.

So far, many experts have proposed some indoor communication methods. For example: an indoor environment mode matrix is constructed to restore an indoor test scene, or a transmitting point and a receiving end are constructed to analyze the change of the scene through a vector network analyzer, so that the high-capacity requirement of indoor communication is met. However, in the methods, the test scene is restored, the structure of a room is ignored, and the arrangement in the room can influence the propagation of signals; meanwhile, these signal blind areas cannot be measured at all by conventional test instruments at the toilet and the corner.

Disclosure of Invention

In view of the above, the present invention provides an indoor signal tracking method, which analyzes indoor scenes in different situations, can solve the problem of uncertainty in signal transmission in the existing indoor communication, and finds an indoor signal blind area by using ray tracing.

The invention adopts the following technical scheme:

an indoor signal tracking method, comprising the steps of:

s1, analyzing the test scene by combining the indoor condition of the test scene and the peripheral outdoor condition;

s2, setting parameters of the transmitting and receiving antenna and the off-grid analyzer according to the analysis result;

s3, simulating the signal coverage condition in the whole room, wherein when the transmitting point and the receiving point belong to line-of-sight transmission, an LEE model is adopted for simulation, and when the transmitting point and the receiving point belong to non-line-of-sight transmission, a CW model is adopted for simulation;

s4, comparing the simulation result with the standard data, judging whether the simulation result is in the standard range, if not, correcting the model parameters until the simulation result reaches the standard;

and S5, completing indoor signal propagation tracking work and determining a signal propagation scheme.

The indoor conditions in the step S1 include confirming wall materials, estimating space loss, surveying the existing signal coverage condition, whether the signal can be directly used, and confirming whether hot spot coverage exists; the outdoor situation comprises the steps of obtaining the wireless environment situation around the test scene, analyzing the mutual influence of the station and the indoor signal coverage, and checking the position of the antenna point.

The visual distance propagation simulation process in step S3 is:

s31, collecting data according to the set model parameters, placing a receiver at the edge of a receiving point for data recording, and calculating the path loss between a transmitting point and the receiving point through a path loss formula to obtain the receiving power of the LEE model;

s32, analyzing whether the received power is in a standard range, if so, meeting the coverage requirement of indoor line-of-sight transmission, and if not, changing the position and input power of the antenna and continuing to simulate the indoor line-of-sight transmission without meeting the coverage requirement of the indoor line-of-sight transmission;

the path loss equation is:

wherein d is₁Is the apparent distance of propagation, λ is the wavelength, h_aFor transmitting antenna height, h_mFor receiving the antenna height, alpha_rFor floor dielectric loss, B for indoorLosses caused by other objects.

And S33, repeating the step S32 until the received power reaches a specified range, namely the simulation result is qualified.

The non-line-of-sight propagation simulation process in step S3 is:

s34, setting parameters of the CW model, selecting a sending point and a receiving point to perform ray tracing of the CW model, namely setting a CW propagation environment, performing signal tracing and combining an electromagnetic environment to obtain receiving power;

s35, judging loss according to the received power of the receiving point, comparing the received power with standard data, if the received power meets the standard, successfully tracing the CW model, if the received power does not meet the standard, correcting the CW model according to the test point and the test route map;

the received power is:

converting the path loss to dB, the ratio between transmit and receive power is obtained as:

where K is the number of rays, U is the number of first reflections occurring, V is the number of second reflections occurring, I is the number of diffractions, d is the distance, P_kIs the k-th ray arrival power, R_uIs the gain, R, of the receiving antenna after the u-th occurrence of two reflections_vIs the gain, T, of the receiving antenna after the v-th occurrence of two reflections_iIs the gain of the transmitting antenna after the ith diffraction.

And S36, repeating the step S35 until the tracking effect of the CW model reaches the standard, namely finishing the signal propagation tracking work and determining the propagation scheme.

Has the advantages that: the invention adopts different models to simulate the indoor communication environment, can observe the indoor layout more clearly, has further mastered the whole indoor system propagation loss through the correction process during the simulation, utilizes the CW ray model to track the signal, finds the coverage condition and the signal blind area of the system, and provides an effective modeling scheme for improving the indoor communication coverage rate and the indoor communication quality. After correction, the CW model can well restore the propagation process of the signal in the test scene, and the data at the receiving end can be used as a reference value, so that the whole signal propagation tracking work has a better result and has better advantage on the indoor signal coverage condition. Compared with the traditional indoor test method, the method subdivides the indoor test scene into an indoor line-of-sight propagation scene and an indoor non-line-of-sight propagation scene, the loss of the indoor non-line-of-sight propagation is more, the CW model system is adopted to better discover the blind area of the signal, and a researcher can conveniently establish a high-precision indoor coverage system on the basis.

Drawings

FIG. 1 is a general flow chart of the present invention;

FIG. 2 is a view of a line of sight propagation;

FIG. 3 is a non-line-of-sight propagation roadmap;

FIG. 4 is a diagram of indoor scene restoration effect;

fig. 5 is a 3D restoration effect diagram of an indoor scene.

Detailed Description

The invention will be further explained and explained in detail with reference to the drawings and the embodiments.

Example 1: in this embodiment, an indoor test scenario is located in a low-floor residence of a certain cell in kunming city, Yunnan, where there are 10 floors in a building, each floor is 3m high, and the distance between buildings is 30m, and a resident generally uses his own mobile phone to communicate, and establishes a clear switching area between a macro network and an indoor network in an area with a large traffic usage amount, such as a living room, a working room, etc., and because buildings are close to each other, overlapping coverage causes interference, so it is necessary to increase outdoor suppression of indoor signals.

Firstly, judging a test scene environment through instruments such as a transmitting antenna, a receiving antenna, a vector network analyzer, a feeder line, a triangular support, a distance meter and the like, wherein from the indoor point of view, wall materials need to be confirmed, space loss is estimated, the existing distribution system condition is surveyed, whether the existing distribution system condition can be directly utilized or not is confirmed, whether hot spot coverage exists or not is confirmed, and indoor layout condition can be simulated by RoomAranger software; and judging from an outdoor scene near the test environment, acquiring the wireless environment condition around the building, analyzing the mutual influence of the site and the indoor coverage system, shooting a panoramic photo of the building, and checking the position of an antenna point.

Indoor coverage simulation test, in order to obtain the most approximate actual data and the optimal antenna position, various analyses are carried out on the test environment, after the antenna position is preset, propagation simulation is carried out,

the indoor signal tracking is carried out on the test scene according to the flow chart shown in fig. 1, and the indoor signal tracking is mainly divided into line-of-sight propagation and non-line-of-sight propagation.

Visual range propagation: and collecting a receipt according to the set parameters, estimating the path loss, measuring the path distance between the transmitting point and the receiving point, calculating according to a proposed path loss formula to obtain the receiving power of the model, wherein the center frequency of the vector network analyzer is 2.4GHZ, the frequency step length is 6MHz, the antenna height is 1.6m, and the receiving antenna height is 0.95 m. Obtaining the most suitable antenna position and feed-in power by changing the position and the input power for many times, and placing a receiver at the edge of a receiving point for data recording; judging the received data, judging whether the measured and collected data meets the coverage requirement of indoor line-of-sight transmission, and if so, indicating that the simulation data experiment is successful; if the requirement is not met, the antenna position and the input power are required to be changed, and the effect evaluation is continued.

Non-line-of-sight propagation: judging whether the coverage of an indoor blind area is achieved, finding a problem area by adopting a method of combining indoor and outdoor stations, and obtaining receiving power according to ray tracing test and electromagnetic environment analysis; judging the tracking effect of the CW propagation model on non-line-of-sight transmission, selecting areas with important functions such as a living room and a corridor as a sending point, selecting important office places such as a bedroom, a study room and an edge adjacent window as a receiving point, starting software after antenna hanging point design is completed, setting a CW propagation environment and carrying out signal tracking analysis; judging the tracking effect of the CW ray, comprehensively processing all sample points when non-line-of-sight propagation is carried out, fitting through original test sample point data, and carrying out contrastive analysis to obtain the tracking effect of the CW simulation test scheme; carrying out model correction on a test point and a test route map for CW propagation, and randomly carrying out signal test on twenty indoor coordinates by using terminal equipment, namely, carrying out further judgment on the indoor signal coverage rate in the continuous test process, wherein if the coverage rate is more than 88%, the propagation process of the signal is well restored by the propagation model, and if the coverage rate is lower than 88%, the tracking process of the model is failed, and a correction process is required; and changing the test position, finishing the signal propagation tracking work, determining a propagation scheme and judging the indoor coverage condition.

The path loss is mainly caused by the reflection phenomenon caused by indoor furniture, unreasonable setting of transmitting power parameters, unreasonable arrangement of antennas and the like, and even if the signal transmission loss is influenced to a certain extent by adjusting indoor layout and replacing furniture made of different materials, the path loss is often analyzed as quantitative loss in the actual communication process.

The roadmap shown in fig. 2-3: after the antenna position is preset, propagation simulation is started, and if signal transmission is performed at time T, in this case, two propagation modes may exist, one is line-of-sight propagation and the other is non-line-of-sight propagation. The sight distance propagation indicates that direct waves and reflected waves caused by articles such as indoor furniture or windows mainly exist between the transmitting point and the receiving point; the non-line-of-sight propagation indicates that a large obstruction exists between the transmitting point and the receiving point, such as diffracted waves and reflected waves caused by walls, doors, cabinets and other objects, and the propagation path needs to further analyze the loss of the waveforms.

For case one, line-of-sight propagation:

ray propagation tests were performed in an empty room using the mirror method, and the propagation process is shown in fig. 2.

The transmitting antenna and the receiving antenna are vertical omnidirectional antennas, a room consists of three walls and a glass window, and the receiving power of a direct path and a reflected path is considered because the room is spacious;

furniture such as sofas, tables, televisions and the like are added, the path of a receiving point is analyzed by using a ray intersection method, all mirror rays are searched, and the influence of personnel walking is ignored.

For case two, non-line-of-sight propagation:

atoll simulation software is used, model correction is carried out, real original signals can be accurately restored by the software when signal tracking is carried out, environments capable of predicting radio wave propagation comprise complex electromagnetic environments such as indoor and mountainous areas, and the propagation process is shown in figure 3.

Emitting rays, wherein electric waves start to propagate with a radius r, and the wave front is positioned on a circular edge surface;

receiving rays, performing reflection and diffraction on the rays to reach a receiving point, defining a mirror surface, judging whether reflection or diffraction exists or not when the rays have intersection points with the mirror surface in the propagation process and are effective intersection points, judging whether the two points are positioned on the same side of a line segment or not by using an intersection operation method, and considering that the rays can reach the receiving point;

and (3) tracking the ray, wherein all propagation paths between the emission point and the receiving point can be found out by a CW ray tracking method, intersection operation is carried out to obtain whether the ray belongs to direct projection, reflection or diffraction, so that the condition of the ray propagation process can be mastered, and signal tracking is realized. The effect of both traces is shown in fig. 4-5.

Although the embodiments of the present invention have been described in conjunction with the accompanying drawings, those skilled in the art may make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations fall within the scope defined by the appended claims.