CN114885401A

CN114885401A - WIFI active scanning method and device, and terminal positioning method and device

Info

Publication number: CN114885401A
Application number: CN202210515468.9A
Authority: CN
Inventors: 徐晓亮; 倪海峰
Original assignee: Nanjing Chuangxin Huilian Technology Co ltd
Current assignee: Nanjing Chuangxin Huilian Technology Co ltd
Priority date: 2022-05-12
Filing date: 2022-05-12
Publication date: 2022-08-09

Abstract

The application provides a WIFI active scanning method and device and a terminal positioning method and device, and the method comprises the following steps: determining a current WIFI channel group to be scanned, which contains M WIFI channels, wherein M is a positive integer greater than or equal to 2; aiming at each WIFI channel in the M WIFI channels, sending an address inquiry request frame to a wireless access node of the WIFI channel by using the WIFI channel; and demodulating the inquiry address response frame sent by the wireless access node of each of the M WIFI channels. Through the scheme in this application, radio frequency and digital power consumption have been reduced, WIFI scanning time has been reduced.

Description

WIFI active scanning method and device, and terminal positioning method and device

Technical Field

The application relates to the technical field of communication, in particular to a WIFI active scanning method and device and a terminal positioning method and device.

Background

After accessing a Long Term Evolution (LTE) network, a terminal of the internet of things (hereinafter referred to as a terminal) has a need to perform positioning assistance by using WIFI, and at this time, BSSID collection and power estimation of a nearby Wireless Access Point (AP) need to be completed by using Wireless Fidelity (WIFI). The terminal sends the collected BSSID and power of the nearby AP to the server, the server can inquire an address matched with the received BSSID and power in a database, and then address information is returned to the terminal, and the function cannot affect normal LTE service.

Common WIFI scanning methods include WIFI passive scanning and WIFI active scanning. The WIFI passive scanning is to passively detect beacon frames broadcast by the AP by the terminal so as to complete the collection of BSSID. The WIFI active scanning is that the terminal sends a Probe request frame, and the terminal receives the Probe response frame sent by the AP end and completes the collection of BSSID. However, the time occupied by the related WIFI passive scanning and WIFI active scanning is long, and the Radio Frequency (RF) on time is long, which is not favorable for the fast scanning of WIFI.

Disclosure of Invention

The present application is proposed to solve the above-mentioned technical problems. The embodiment of the application provides a WIFI active scanning method and device and a terminal positioning method and device.

In a first aspect, an embodiment of the present application provides a WIFI active scanning method, including: determining a current WIFI channel group to be scanned, which contains M WIFI channels, wherein M is a positive integer greater than or equal to 2; aiming at each WIFI channel in the M WIFI channels, sending an address inquiry request frame to a wireless access node of the WIFI channel by using the WIFI channel; and demodulating the inquiry address response frame sent by the wireless access node of each of the M WIFI channels.

With reference to the first aspect, in some implementations of the first aspect, determining a current WIFI channel group to be scanned that includes M WIFI channels includes: respectively carrying out initialization configuration on N candidate WIFI channel groups in an idle state time period of LTE to obtain N initialization channel groups, wherein N is a positive integer; selecting an undetected initialization channel group from the N initialization channel groups as a WIFI channel group to be detected; if the WIFI channels contained in the WIFI channel group to be detected correspond to the wireless access nodes, determining the WIFI channel group to be detected as a current WIFI channel group to be scanned; and if the WIFI channel group to be detected contains a WIFI channel without the wireless access node, continuously performing initialization configuration on the N candidate WIFI channel groups respectively until the obtained WIFI channels contained in the WIFI channel group to be detected respectively correspond to the wireless access node.

With reference to the first aspect, in certain implementations of the first aspect, for each WIFI channel of the M WIFI channels, the number of execution times of sending, by using the WIFI channel, the address request frame to the wireless access node of the WIFI channel is at least two.

With reference to the first aspect, in certain implementations of the first aspect, the sending the address request frame to the wireless access node of the WIFI channel by using the WIFI channel includes: generating an initial Probe request frame in a MAC frame format; carrying out spread spectrum, oversampling and shaping filtering operation on the initial Probe request frame to generate a Probe request frame; and based on a time division multiplexing mode, utilizing a WIFI channel to send a Probe request frame to the wireless access node.

With reference to the first aspect, in certain implementations of the first aspect, the demodulating, by the wireless access node of each of the M WIFI channels, the address query response frame includes a Probe response frame, and includes: respectively carrying out digital-to-analog conversion, down sampling and molding filtering operation on the Probe response frames sent by the wireless access nodes of the M WIFI channels to obtain initial processing Probe response frames corresponding to the M WIFI channels; reading initial processing Probe response frames corresponding to the M WIFI channels by using WIFI software in the terminal; and respectively carrying out detection and demodulation based on frequency offset estimation on the primary processing Probe response frames corresponding to the M WIFI channels.

With reference to the first aspect, in some implementation manners of the first aspect, the performing detection and demodulation based on frequency offset estimation on the initially processed Probe response frames corresponding to the M WIFI channels respectively includes:

for each WIFI channel in the M WIFI channels, carrying out sampling rate conversion on the primary processing Probe response frame corresponding to the WIFI channel to generate a second processing Probe response frame corresponding to the WIFI channel; carrying out frequency shifting on the second processing Probe response frame corresponding to the WIFI channel to obtain a third processing Probe response frame corresponding to the WIFI channel; and detecting and demodulating a third processed Probe response frame corresponding to the WIFI channel based on frequency offset estimation.

With reference to the first aspect, in some implementation manners of the first aspect, the performing detection and demodulation based on frequency offset estimation on a third processed Probe response frame corresponding to a WIFI channel includes: if the third processed Probe response frame is determined to be equal to the preset rate, detecting a long lead code in the third processed Probe response frame corresponding to the WIFI channel based on frequency offset estimation to obtain a detection result, and determining at least two sampling points corresponding to the long lead code to obtain a sampling result; if the third processing Probe response frame is determined not to be equal to the preset rate, detecting a long lead code and a short lead code in the third processing Probe response frame corresponding to the WIFI channel based on frequency offset estimation to obtain a detection result, and determining at least two sampling points corresponding to the long lead code and the short lead code to obtain a sampling result; and if the third processing Probe response frame corresponding to the WIFI channel is determined to be the Probe response frame based on the detection result and the sampling result, analyzing the format of the Probe response frame, and reporting the BSSID and the frame power.

In a second aspect, an embodiment of the present application provides a terminal positioning method, including: executing the WIFI active scanning method in the first aspect by using a terminal to be positioned to obtain a scanning result; and determining the position information of the terminal to be positioned based on the scanning result.

In a third aspect, an embodiment of the present application provides a WIFI active scanning apparatus, including: the device comprises a first determining module, a second determining module and a scanning module, wherein the first determining module is used for determining a current WIFI channel group to be scanned, which contains M WIFI channels, and M is a positive integer greater than or equal to 2; the device comprises a sending module, a receiving module and a sending module, wherein the sending module is used for sending an address inquiry request frame to a wireless access node of a WIFI channel by utilizing the WIFI channel aiming at each WIFI channel in M WIFI channels; and the demodulation module is used for demodulating the address inquiry response frame sent by the wireless access node of each of the M WIFI channels.

In a fourth aspect, an embodiment of the present application provides a terminal positioning apparatus, including: the second determining module is used for executing the WIFI active scanning method in the first aspect by using the terminal to be positioned to obtain a scanning result; and the third determining module is used for determining the position information of the terminal to be positioned based on the scanning result.

Based on the WIFI active scanning method provided by the embodiment of the application, the terminal sends the address inquiry request frame to the wireless access node of the WIFI channel through at least two WIFI channels every time, so that the WIFI transmission time and the RF starting time can be reduced, and meanwhile, the radio frequency and the power consumption of the terminal can be reduced.

Drawings

The above and other objects, features and advantages of the present application will become more apparent by describing in more detail embodiments of the present application with reference to the attached drawings. The accompanying drawings are included to provide a further understanding of the embodiments of the application and are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description serve to explain the principles of the application. In the drawings, like reference numbers generally represent like parts or steps.

Fig. 1 is a schematic flowchart illustrating a WIFI active scanning method according to an exemplary embodiment of the present disclosure.

Fig. 2 is a schematic flowchart illustrating a process of determining a current WIFI channel group to be scanned, which includes M WIFI channels according to an exemplary embodiment of the present application.

Fig. 3 is a schematic flowchart illustrating a process of sending an address request frame to a wireless access node of a WIFI channel according to an exemplary embodiment of the present application.

Fig. 4 is a schematic flowchart illustrating a process of demodulating an address query response frame sent by a wireless access node of each of M WIFI channels according to an exemplary embodiment of the present application.

Fig. 5 is a schematic flow chart illustrating detection and demodulation based on frequency offset estimation for the initial Probe response frames corresponding to M WIFI channels respectively according to an exemplary embodiment of the present application.

Fig. 6 is a schematic structural diagram illustrating demodulation of three address response frames according to an exemplary embodiment of the present application.

Fig. 7 is a schematic flow chart illustrating detection and demodulation based on the frequency offset estimation performed on a third processed Probe response frame corresponding to a WIFI channel according to an exemplary embodiment of the present application.

Fig. 8 is a schematic structural diagram illustrating a Probe detect unit parsing third processing Probe response according to an exemplary embodiment of the present application.

Fig. 9 is a flowchart illustrating a terminal positioning method according to an exemplary embodiment of the present application.

Fig. 10 is a schematic structural diagram of a WIFI active scanning apparatus according to an exemplary embodiment of the present application.

Fig. 11 is a schematic structural diagram of a terminal positioning apparatus according to an exemplary embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The terminal has the requirement of utilizing WIFI to carry out auxiliary positioning after accessing the LTE network, at the moment, the WIFI is required to be used for scanning and finishing the collection and power estimation of BSSID of nearby AP, and the terminal is positioned based on the BSSID and the power of the AP. Common WIFI scanning methods include WIFI active scanning and WIFI passive scanning, where the WIFI active scanning takes a short time compared to the WIFI passive scanning. However, in the related art, when WIFI actively scans, a Probe response frame is usually sent based on one WIFI channel, which increases the WIFI search time and increases the power consumption of the terminal.

Fig. 1 is a schematic flowchart illustrating a WIFI active scanning method according to an exemplary embodiment of the present disclosure. Illustratively, the WIFI active scanning method is applied to a terminal positioning system. As shown in fig. 1, the WIFI active scanning method provided in the embodiment of the present application includes the following steps.

And step 10, determining a current WIFI channel group to be scanned, which contains M WIFI channels.

M is a positive integer greater than or equal to 2.

Specifically, M WIFI channels included in the current WIFI channel group to be scanned may be adjacent channels or non-adjacent channels. The current WIFI channel group to be scanned can contain 2 WIFI channels, and also can contain 3 WIFI channels or any number of other WIFI channels larger than 2.

Illustratively, there are 11 WIFI channels, which are WIFI channel 1, WIFI channel 2, WIFI channel 3, WIFI channel 4, WIFI channel 5, WIFI channel 6, WIFI channel 7, WIFI channel 8, WIFI channel 9, WIFI channel 10, and WIFI channel 11, respectively. The current WIFI channel group to be scanned comprises a WIFI channel 1 and a WIFI channel 2; or the current WIFI channel group to be scanned comprises a WIFI channel 2 and a WIFI channel 7; or the current WIFI channel group to be scanned comprises a WIFI channel 4, a WIFI channel 5 and a WIFI channel 6; or the current WIFI channel group to be scanned comprises a WIFI channel 4, a WIFI channel 6 and a WIFI channel 10.

A person skilled in the art can select a specific number of WIFI channels in the current WIFI channel group to be scanned and whether M WIFI channels in the current WIFI channel group to be scanned are adjacent, which is not specifically limited in this embodiment of the present application.

And 20, aiming at each WIFI channel in the M WIFI channels, sending an address inquiry request frame to a wireless access node of the WIFI channel by using the WIFI channel.

The address inquiry request frame belongs to a management frame in the WIFI network and is mainly used for searching for the position information of the AP on the WIFI channel, so that the address inquiry request frame comprises address request information, and the address request information can request one or more parameters related to the AP in the WIFI channel.

Illustratively, the current WIFI channel group to be scanned includes WIFI channel 4, WIFI channel 5, and WIFI channel 6. Meanwhile, the WIFI channel 4, the WIFI channel 5 and the WIFI channel 6 are opened, the terminal sends the address inquiry request frame to the AP on the corresponding WIFI channel sequentially through the WIFI channel 4, the WIFI channel 5 and the WIFI channel 6 within a set time, namely, the time for sending the address inquiry request frame through the WIFI channel 4, the WIFI channel 5 and the WIFI channel 6 is staggered, so that frequency interference on different WIFI channels is prevented.

And step 30, demodulating the inquiry address response frame sent by the wireless access node of each of the M WIFI channels.

The address response frame is a response frame returned by the AP on the WIFI channel and containing the location information of the AP. By detecting and demodulating the inquiry address response frame, the position information of the AP in the corresponding WIFI channel can be obtained.

Different from the method that one WIFI channel is opened within a set time, and the address inquiry request frame is sent to the AP in the WIFI channel through the WIFI channel, the address inquiry frame is sent to the AP in the WIFI channel sequentially through at least two WIFI channels each time in the embodiment of the application. Through the technical scheme in the embodiment of the application, the design of the WIFI transceiver can be reduced, the AP search time is reduced, and the power consumption of the terminal is reduced.

Fig. 2 is a schematic flowchart illustrating a process of determining a current WIFI channel group to be scanned, which includes M WIFI channels according to an exemplary embodiment of the present application. The embodiment shown in fig. 2 is extended based on the embodiment shown in fig. 1, and the differences between the embodiment shown in fig. 2 and the embodiment shown in fig. 1 will be emphasized below, and the descriptions of the same parts will not be repeated.

As shown in fig. 2, determining a current WIFI channel group to be scanned, which includes M WIFI channels, includes the following steps.

And 11, respectively carrying out initialization configuration on the N candidate WIFI channel groups in the idle state time period of the LTE to obtain N initialization channel groups.

N is a positive integer.

Specifically, in an idle state period of LTE, N WIFI channel candidates are initially configured, that is, Automatic Gain Control (AGC), to obtain N initialization channel groups.

And step 12, selecting an undetected initialization channel group from the N initialization channel groups as a WIFI channel group to be detected.

And step 13, judging whether the WIFI channels contained in the WIFI channel group to be detected correspond to the wireless access nodes respectively.

The undetected initialization channel group means that whether an AP exists in a WIFI channel included in the initialization channel group is not detected.

Specifically, the idle state of the WIFI channel in the to-be-detected WIF channel group can be monitored, and whether the carrier detection is triggered by the WIFI channel in the to-be-detected WIFI channel group within a protection time is detected. If the WIFI channel does not trigger carrier detection, determining that the WIFI channel without the AP exists in the WIFI channel group to be detected; and if each WIFI channel in the WIFI channel group to be detected triggers carrier detection, determining that the WIFI channels in the WIFI channel group to be detected all have respective corresponding APs. Wherein the protection time is Probe delay time.

Illustratively, N is equal to 3, that is, there are 3 initialization channel groups, and the first initialization channel group has already been detected, the second initialization channel group may continue to be used as the WIFI channel group to be detected, so as to perform the detection in the next stage. For the WIFI channel 1, the WIFI channel 2 and the WIFI channel 3 in the second initialization channel group, detecting whether carrier detection is triggered on the WIFI channel 1, the WIFI channel 2 and the WIFI channel 3 or not in idle states of the WIFI channel 1, the WIFI channel 2 and the WIFI channel 3, and if carrier detection is triggered on the WIFI channel 1, the WIFI channel 2 and the WIFI channel 3, judging that the WIFI channel 1, the WIFI channel 2 and the WIFI channel 3 in the second initialization channel group all have corresponding APs; and if one WIFI channel of the WIFI channel 1, the WIFI channel 2 and the WIFI channel 3 does not trigger carrier detection, judging that the second initialization channel group has the WIFI channel which does not contain the AP.

Exemplarily, in an actual application process, if the determination result in step 13 is yes, that is, the WIFI channels included in the to-be-detected WIFI channel group are respectively corresponding to the wireless access node, step 14 is executed, and if the determination result in step 22 is no, that is, the to-be-detected WIFI channel group includes a WIFI channel without a wireless access node, step 15 is executed.

And step 14, determining the WIFI channel group to be detected as the current WIFI channel group to be scanned.

And step 15, continuing to perform initialization configuration on the N candidate WIFI channel groups respectively until the obtained WIFI channels included in the WIFI channel group to be detected correspond to the wireless access nodes respectively.

In this embodiment, first, the N WIFI channel candidates are initially configured in the idle state period of LTE, which does not interfere with the LTE main service. Secondly, whether carrier detection is triggered by the WIFI channel or not is detected, whether the WIFI channel group to be detected can be used as the current WIFI channel group to be scanned to send an address inquiry request frame or not can be conveniently and accurately judged.

In an exemplary embodiment, for each WIFI channel of the M WIFI channels, sending an addressing request frame to a wireless access node of the WIFI channel using the WIFI channel is performed at least twice.

Specifically, in order to prevent the AP in the WIFI channel from not receiving the address requesting frame sent by the terminal in time, the step of sending the address requesting frame to the wireless access node of the WIFI channel by using the WIFI channel may be performed multiple times.

Fig. 3 is a schematic flowchart illustrating a process of sending an address request frame to a wireless access node of a WIFI channel according to an exemplary embodiment of the present application. The embodiment shown in fig. 3 is extended based on the embodiment shown in fig. 1, and the differences between the embodiment shown in fig. 3 and the embodiment shown in fig. 1 will be emphasized below, and the descriptions of the same parts will not be repeated.

As shown in fig. 3, the address response frame includes a Probe response frame, and the address request frame is sent to the wireless access node of the WIFI channel by using the WIFI channel, including the following steps.

And step 21, generating an initial Probe request frame in the MAC frame format.

And step 22, performing spreading, oversampling and shaping filtering operation on the initial Probe request frame to generate the Probe request frame.

Specifically, a 1/2Mbps mode of DSSS is adopted, DBPSK plus barker spreading or DQPSK plus barker spreading is carried out on an initial Probe request frame, then the initial Probe request frame after spreading is subjected to oversampling to a preset value, and then the initial Probe request frame after oversampling is subjected to shaping filtering operation, so that the Probe request frame is obtained. Wherein the preset value is 30.72M.

And storing the waveform of the Probe request frame by adopting fixed data, and directly sending the baseband signal data of the waveform of the Probe request frame to the LTE hardware equipment when the Probe request frame is sent. After the LTE hardware device performs upsampling on a Probe request frame, a sending unit (Transport, TX) side of the LTE configures preset digital domain power and analog domain gain, so that the TX power reaches a WIFI specification, and an Error Vector Magnitude (EVM) is controlled within a controllable range.

And step 23, based on a time division multiplexing mode, sending a Probe request frame to the wireless access node by using the WIFI channel.

Specifically, after the switching-in is performed to the frequency point corresponding to the WIFI channel in the current WIFI channel group to be scanned, the forward link receiver and the reverse link receiver continuously detect the power value of the signal on the WIFI channel in the current WIFI channel group to be scanned, and if the signal power on the WIFI channel in the current WIFI channel group to be scanned is always lower than the preset power within a certain time period, that is, within the time period of DIFSS + complete backoff window, it is determined that no service transmission exists on the WIFI channel in the current WIFI channel group to be scanned, and at this time, based on a time division multiplexing mode, the Probe request frame is sent to the AP by using the WIFI channel.

In this embodiment, before the Probe request frame is sent to the AP by using the WIFI channel, it is monitored in advance whether other stations on the WIFI channel are transmitting messages. When the WIFI channel is not occupied by the services of other sites, the WIFI channel is reused to send a Probe request frame to the AP, so that mutual interference of different services on the WIFI channel is avoided. In addition, the Probe request frames are sent to the APs on the WIFI channels in a time division multiplexing mode, that is, a fixed transmission time slot is allocated to each WIFI channel, and the Probe request frames are sent to the APs on the WIFI channels in sequence at a uniform time interval, so that mutual interference of signals on different WIFI channels is further avoided.

Fig. 4 is a schematic flowchart illustrating a process of demodulating an address query response frame sent by a wireless access node of each of M WIFI channels according to an exemplary embodiment of the present application. The embodiment shown in fig. 4 is extended based on the embodiment shown in fig. 1, and the differences between the embodiment shown in fig. 4 and the embodiment shown in fig. 1 will be emphasized below, and the descriptions of the same parts will not be repeated.

As shown in fig. 4, the polling response frame includes a Probe response frame, and the polling response frame transmitted by the wireless access node of each of the M WIFI channels is demodulated, including the following steps.

And step 31, respectively performing digital-to-analog conversion, down sampling and forming filtering operations on the Probe response frames sent by the wireless access nodes of the M WIFI channels to obtain initial processing Probe response frames corresponding to the M WIFI channels.

Preferably, the step of sending the Probe response frames by the APs on the M WIFI channels is also repeated at least twice, so as to prevent the terminals from missing Probe response frames sent by the APs on the M WIFI channels.

After the Probe response frame is sent, a receiving unit (Receive, RX) path of the LTE is opened, a preset carrier is configured, and data of the Probe response frame is collected at an LTE hardware outlet to a storage unit. Illustratively, the Memory unit is a Random Access Memory (RAM).

And step 32, reading the initial processing Probe response frames corresponding to the M WIFI channels by using WIFI software in the terminal.

Specifically, data on Probe response frames in the storage unit is read by using WIFI software.

And step 33, respectively performing detection and demodulation based on frequency offset estimation on the initially processed Probe response frames corresponding to the M WIFI channels.

By the technical scheme in the embodiment, the terminal can be prevented from missing detection of the Probe response frame sent by the AP end. In addition, the initial processing Probe response frames corresponding to the M WIFI channels are detected and demodulated based on frequency offset estimation, so that the interference of the WIFI channels can be identified, and the false detection rate of the initial processing Probe response frames is reduced.

Fig. 5 is a schematic flow chart illustrating detection and demodulation based on frequency offset estimation for the initial Probe response frames corresponding to M WIFI channels respectively according to an exemplary embodiment of the present application. The embodiment shown in fig. 5 is extended based on the embodiment shown in fig. 4, and the differences between the embodiment shown in fig. 5 and the embodiment shown in fig. 4 will be emphasized below, and the descriptions of the same parts will not be repeated.

As shown in fig. 5, the detection and demodulation based on frequency offset estimation are performed on the initially processed Probe response frames corresponding to the M WIFI channels, respectively, including the following steps.

Step 331, for each WIFI channel of the M WIFI channels, performing sampling rate conversion on the Probe response frames initially processed corresponding to the WIFI channel, and generating a second processed Probe response frame corresponding to the WIFI channel.

And step 332, carrying out frequency shifting on the second processed Probe response frame corresponding to the WIFI channel to obtain a third processed Probe response frame corresponding to the WIFI channel.

And 333, detecting and demodulating a third processed Probe response frame corresponding to the WIFI channel based on frequency offset estimation.

Through the technical scheme in the embodiment, mutual interference of different initially processed Probe response frames in M WIFI channels can be avoided, and the accuracy of detection of the initially processed Probe response frames is improved.

As shown in fig. 6, the structure includes an LTE hardware module and a WIFI software module, where the LTE hardware module includes an ADC unit, a download unit, and a Fir unit; the WIFI software module comprises an Sfc unit, three DDC units and three Probe detect units which are in one-to-one correspondence with the three DDC units respectively. The number of the DDC units and the number of the Probe detect units correspond to the number of the WIFI channels contained in the WIFI channel group to be scanned currently, for example, the WIFI channel group to be scanned currently contains three WIFI channels, and then three Probe detect units of three DDC units are needed.

Illustratively, the LTE hardware module performs digital-to-analog conversion, down-sampling and shape filtering operations on Probe response frames transmitted by APs of respective three WIFI channels. The Sfc unit completes the conversion of the sampling rate of the initially processed Probe response frames, the three DDC units complete the frequency shifting of the initially processed Probe response frames on the three WIFI channels, and the three Probe detect units complete the detection and demodulation of the initially processed Probe response frames on the three WIFI channels.

Fig. 7 is a schematic flow chart illustrating detection and demodulation based on the frequency offset estimation performed on a third processed Probe response frame corresponding to a WIFI channel according to an exemplary embodiment of the present application. The embodiment shown in fig. 7 is extended based on the embodiment shown in fig. 5, and the differences between the embodiment shown in fig. 7 and the embodiment shown in fig. 5 will be emphasized below, and the descriptions of the same parts will not be repeated.

As shown in fig. 7, the third processed Probe response frame corresponding to the WIFI channel is detected and demodulated based on the frequency offset estimation, which includes the following steps.

Step 3331, determine whether the third processed Probe response frame is equal to the predetermined rate.

Illustratively, the predetermined rate is a 1mbps rate.

It is understood that the preset rate in this example is only an example, and those skilled in the art can select a specific preset rate according to actual situations.

For example, in the actual application process, if the determination result in step 3331 is yes, that is, the third processed Probe response frame is equal to the predetermined rate, step 3332 is executed. If the determination result in the step 3331 is "no", that is, the third processed Probe response frame is not equal to the preset rate, then step 3333 is executed.

Step 3332, detecting the long lead code in the third processed Probe response frame corresponding to the WIFI channel based on the frequency offset estimation to obtain a detection result, and determining at least two sampling points corresponding to the long lead code to obtain a sampling result.

Step 3333, detecting the long preamble and the short preamble in the third processed Probe response frame corresponding to the WIFI channel based on the frequency offset estimation to obtain a detection result, and determining at least two sampling points corresponding to the long preamble and the short preamble to obtain a sampling result.

Specifically, through

steps

3332 and 3333, the detection result and the sampling result of the long preamble with respect to the third processed Probe response frame, or the long preamble plus the short preamble with respect to the third processed Probe response frame can be obtained.

Step 3334, based on the detection result and the sampling result, determining whether the third processed Probe response frame corresponding to the WIFI channel is a Probe response frame.

Specifically, whether the third processed Probe response frame corresponding to the WIFI channel is a Probe response frame is determined according to the detection result and the sampling result in step 3332 or step 3333.

For example, in an actual application process, if the determination result in the step 3334 is yes, that is, the third processed Probe response frame corresponding to the WIFI channel is a Probe response frame, the step 3335 is executed. If the determination result in the step 3334 is negative, that is, the third processed Probe response frame corresponding to the WIFI channel is not a Probe response frame, then step 3336 is executed.

Step 3335, parsing the format of the Probe response frame, and reporting the BSSID and the frame power.

Step 3336, the format of the Probe response frame is not parsed.

In this embodiment, when sampling the long preamble of the third processed Probe response frame or the long preamble plus the short preamble of the third processed Probe response frame, the sampling result is determined based on at least two sampling points, so that a more accurate sampling result can be obtained.

As shown in FIG. 8, the Probe detect unit comprises a Corr0 subunit, a Corr1 subunit and a Judge subunit. Wherein the Corr0 subunit, Corr1 subunit and Judge subunit complete the determination of the long preamble, or the long preamble plus the short preamble of the third processed Probe response frame. The desbeam subunit completes the de-spreading of the third processed Probe response frame, the demod subunit completes the demodulation and judgment of the DBPSK or DQPSK of the third processed Probe response frame, the desramble subunit completes the de-scrambling of the third processed Probe response frame, and the crc subunit completes the crc check of the third processed Probe response frame, wherein the header crc subunit checks the header which can resolve the frame after passing to determine the length of the mpdu, the mpdu crc subunit checks the parsed mpdu after passing to judge whether the third processed Probe response frame is a Probe response frame, if so, resolves the frame format, and reports the BSSID and the frame power.

Fig. 9 is a flowchart illustrating a terminal positioning method according to an exemplary embodiment of the present application. As shown in fig. 9, the terminal positioning method provided in the embodiment of the present application includes the following steps.

And 100, executing the WIFI active scanning method by using a terminal to be positioned to obtain a scanning result.

And 200, determining the position information of the terminal to be positioned based on the scanning result.

Through the technical scheme in the embodiment, the terminal to be positioned can be quickly and accurately positioned.

Method embodiments of the present application are described in detail above in conjunction with fig. 1-9, and apparatus embodiments of the present application are described in detail below in conjunction with fig. 10 and 11. It is to be understood that the description of the method embodiments corresponds to the description of the apparatus embodiments, and therefore reference may be made to the preceding method embodiments for parts not described in detail.

Fig. 10 is a schematic structural diagram of a WIFI active scanning apparatus according to an exemplary embodiment of the present application. As shown in fig. 9, the WIFI active scanning apparatus provided in the embodiment of the present application includes:

a first determining module 1010, configured to determine a current WIFI channel group to be scanned, where the current WIFI channel group includes M WIFI channels, where M is a positive integer greater than or equal to 2;

a sending module 1020, configured to send, by using a WIFI channel, an address query request frame to a wireless access node of the WIFI channel for each WIFI channel in the M WIFI channels;

the demodulation module 1030 is configured to demodulate an address query response frame sent by each wireless access node of the M WIFI channels.

In an embodiment of the present application, the first determining module 1010 is further configured to, in an idle state period of LTE, perform initialization configuration on N candidate WIFI channel groups, respectively, to obtain N initialization channel groups, where N is a positive integer; selecting an undetected initialization channel group from the N initialization channel groups as a WIFI channel group to be detected; if the WIFI channels contained in the WIFI channel group to be detected correspond to the wireless access nodes, determining the WIFI channel group to be detected as a current WIFI channel group to be scanned; and if the WIFI channel group to be detected contains a WIFI channel without the wireless access node, continuously performing initialization configuration on the N candidate WIFI channel groups respectively until the obtained WIFI channels contained in the WIFI channel group to be detected respectively correspond to the wireless access node.

In an embodiment of the present application, the sending module 1020 is further configured to, for each WIFI channel in the M WIFI channels, send, by using the WIFI channel, the address query request frame to the wireless access node of the WIFI channel for at least two times.

In an embodiment of the present application, the sending module 1020 is further configured to generate an initial Probe request frame in a MAC frame format; carrying out spread spectrum, oversampling and shaping filtering operation on the initial Probe request frame to generate a Probe request frame; and based on a time division multiplexing mode, utilizing a WIFI channel to send a Probe request frame to the wireless access node.

In an embodiment of the present application, the demodulation module 1030 is further configured to perform digital-to-analog conversion, down-sampling, and shaping filtering operations on Probe response frames sent by respective wireless access nodes of the M WIFI channels, respectively, to obtain initial processing Probe response frames corresponding to the M WIFI channels, respectively; reading initial processing Probe response frames corresponding to the M WIFI channels by using WIFI software in the terminal; and respectively carrying out detection and demodulation based on frequency offset estimation on the primary processing Probe response frames corresponding to the M WIFI channels.

In an embodiment of the present application, the demodulation module 1030 is further configured to, for each WIFI channel in the M WIFI channels, perform sampling rate conversion on the Probe response frame initially processed corresponding to the WIFI channel, and generate a second processed Probe response frame corresponding to the WIFI channel; carrying out frequency shifting on the second processing Probe response frame corresponding to the WIFI channel to obtain a third processing Probe response frame corresponding to the WIFI channel; and detecting and demodulating a third processed Probe response frame corresponding to the WIFI channel based on frequency offset estimation.

In an embodiment of the present application, the demodulation module 1030 is further configured to, if it is determined that the third processed Probe response frame is equal to the preset rate, perform detection based on frequency offset estimation on the long preamble in the third processed Probe response frame corresponding to the WIFI channel to obtain a detection result, and determine at least two sampling points corresponding to the long preamble to obtain a sampling result; if the third processing Probe response frame is determined not to be equal to the preset rate, detecting a long lead code and a short lead code in the third processing Probe response frame corresponding to the WIFI channel based on frequency offset estimation to obtain a detection result, and determining at least two sampling points corresponding to the long lead code and the short lead code to obtain a sampling result; and if the third processing Probe response frame corresponding to the WIFI channel is determined to be the Probe response frame based on the detection result and the sampling result, analyzing the format of the Probe response frame, and reporting the BSSID and the frame power.

Fig. 11 is a schematic structural diagram of a terminal positioning apparatus according to an exemplary embodiment of the present application. As shown in fig. 11, the terminal positioning apparatus provided in the embodiment of the present application includes:

the second determining module 1110 is configured to execute the foregoing WIFI active scanning method by using a terminal to be positioned, so as to obtain a scanning result;

a third determining module 1120, configured to determine, based on the scanning result, location information of the terminal to be located.

The foregoing describes the general principles of the present application in conjunction with specific embodiments, however, it is noted that the advantages, effects, etc. mentioned in the present application are merely examples and are not limiting, and they should not be considered essential to the various embodiments of the present application. Furthermore, the foregoing disclosure of specific details is for the purpose of illustration and description and is not intended to be limiting, since the foregoing disclosure is not intended to be exhaustive or to limit the disclosure to the precise details disclosed.

The block diagrams of devices, apparatuses, systems referred to in this application are only given as illustrative examples and are not intended to require or imply that the connections, arrangements, configurations, etc. must be made in the manner shown in the block diagrams. These devices, apparatuses, devices, systems may be connected, arranged, configured in any manner, as will be appreciated by those skilled in the art. Words such as "including," "comprising," "having," and the like are open-ended words that mean "including, but not limited to," and are used interchangeably herein. The words "or" and "as used herein mean, and are used interchangeably with, the word" and/or, "unless the context clearly dictates otherwise. The word "such as" is used herein to mean, and is used interchangeably with, the phrase "such as but not limited to".

It should also be noted that in the devices, apparatuses, and methods of the present application, the components or steps may be decomposed and/or recombined. These decompositions and/or recombinations are to be considered as equivalents of the present application.

The previous description of the disclosed aspects is provided to enable any person skilled in the art to make or use the present application. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects without departing from the scope of the application. Thus, the present application is not intended to be limited to the aspects shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

The foregoing description has been presented for purposes of illustration and description. Furthermore, the description is not intended to limit embodiments of the application to the form disclosed herein. While a number of example aspects and embodiments have been discussed above, those of skill in the art will recognize certain variations, modifications, alterations, additions and sub-combinations thereof.

Claims

1. A WIFI active scanning method is characterized by comprising the following steps:

determining a current WIFI channel group to be scanned, which contains M WIFI channels, wherein M is a positive integer greater than or equal to 2;

for each WIFI channel in the M WIFI channels, utilizing the WIFI channel to send an addressing request frame to a wireless access node of the WIFI channel;

and demodulating the inquiry address response frame sent by the wireless access node of each of the M WIFI channels.

2. The active WIFI scanning method of claim 1, wherein the determining a current WIFI channel group to be scanned containing M WIFI channels comprises:

respectively carrying out initialization configuration on N candidate WIFI channel groups in an idle state time period of LTE to obtain N initialization channel groups, wherein N is a positive integer;

selecting an undetected initialization channel group from the N initialization channel groups as a WIFI channel group to be detected;

if the WIFI channels contained in the WIFI channel group to be detected correspond to wireless access nodes, determining the WIFI channel group to be detected as the current WIFI channel group to be scanned;

and if the WIFI channel group to be detected contains a WIFI channel without a wireless access node, continuously performing initialization configuration on the N candidate WIFI channel groups respectively until the obtained WIFI channels contained in the WIFI channel group to be detected respectively correspond to the wireless access node.

3. The WIFI active scanning method of claim 1, wherein for each WIFI channel of the M WIFI channels, sending an addressing request frame to a wireless access node of the WIFI channel using the WIFI channel is performed at least twice.

4. The WIFI active scanning method of claim 1, wherein the inquiry request frame comprises a Probe request frame, and wherein the sending an inquiry request frame to a wireless access node of the WIFI channel using the WIFI channel comprises:

generating an initial Probe request frame in a MAC frame format;

performing spreading, oversampling and shaping filtering operations on the initial Probe request frame to generate the Probe request frame;

and based on a time division multiplexing mode, the Probe request frame is sent to the wireless access node by utilizing the WIFI channel.

5. The WIFI active scanning method of any one of claims 1 to 4, wherein the polling response frame includes a Probe response frame, and the demodulating the polling response frame sent by the wireless access node of each of the M WIFI channels includes:

respectively carrying out digital-to-analog conversion, down sampling and molding filtering operation on the Probe response frames sent by the wireless access nodes of the M WIFI channels to obtain initial processing Probe response frames corresponding to the M WIFI channels;

utilizing WIFI software in the terminal to read the initial processing Probe response frames corresponding to the M WIFI channels respectively;

and respectively carrying out detection and demodulation based on frequency offset estimation on the initial processing Probe response frames corresponding to the M WIFI channels.

6. The active scanning method for WIFI according to claim 5, wherein the performing detection and demodulation based on frequency offset estimation on the respective initial processed Probe response frames corresponding to the M WIFI channels respectively includes:

for each of the M WIFI channels,

performing sampling rate conversion on the initially processed Probe response frame corresponding to the WIFI channel to generate a second processed Probe response frame corresponding to the WIFI channel;

carrying out frequency shifting on the second processing Probe response frame corresponding to the WIFI channel to obtain a third processing Probe response frame corresponding to the WIFI channel;

and detecting and demodulating a third processed Probe response frame corresponding to the WIFI channel based on the frequency offset estimation.

7. The active scanning method for WIFI of claim 6, wherein the detecting and demodulating based on the frequency offset estimation third processed Probe response frame corresponding to the WIFI channel comprises:

if the third processing Probe response frame is determined to be equal to the preset rate, detecting a long lead code in the third processing Probe response frame corresponding to the WIFI channel based on the frequency offset estimation to obtain a detection result, and determining at least two sampling points corresponding to the long lead code to obtain a sampling result;

if the third processing Probe response frame is determined not to be equal to the preset rate, detecting a long lead code and a short lead code in the third processing Probe response frame corresponding to the WIFI channel based on the frequency offset estimation to obtain a detection result, and determining at least two sampling points corresponding to the long lead code and the short lead code to obtain a sampling result;

and if the third processing Probe response frame corresponding to the WIFI channel is determined to be the Probe response frame based on the detection result and the sampling result, analyzing the format of the Probe response frame, and reporting the BSSID and the frame power.

8. A terminal positioning method is characterized by comprising the following steps:

executing the WIFI active scanning method according to any one of claims 1 to 7 by using a terminal to be positioned to obtain a scanning result;

and determining the position information of the terminal to be positioned based on the scanning result.

9. A WIFI active scanning device, comprising:

the device comprises a first determining module, a second determining module and a scanning module, wherein the first determining module is used for determining a current WIFI channel group to be scanned, which contains M WIFI channels, and M is a positive integer greater than or equal to 2;

the sending module is used for sending an address inquiry request frame to a wireless access node of the WIFI channel by utilizing the WIFI channel aiming at each WIFI channel in the M WIFI channels;

and the demodulation module is used for demodulating the address inquiry response frame sent by the wireless access node of each of the M WIFI channels.

10. A terminal positioning device, comprising:

a second determining module, configured to execute the WIFI active scanning method according to any one of claims 1 to 7 by using a terminal to be located, so as to obtain a scanning result;

and the third determining module is used for determining the position information of the terminal to be positioned based on the scanning result.