CN113747413A - Multi-network multi-mode vehicle-mounted emergency call method, system and medium - Google Patents
Multi-network multi-mode vehicle-mounted emergency call method, system and medium Download PDFInfo
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Abstract
The application discloses a multi-network multi-mode vehicle-mounted emergency call method, and belongs to the field of wireless communication. The method mainly comprises the steps that according to the signal quality of the network, one operator network with the highest signal quality is selected from a plurality of operator networks to serve as a current dial-up network, and a network mode with the highest network quality is selected from a plurality of network modes of the current dial-up network to serve as a current network mode; and dialing the emergency call in the current network mode of the current dial-up network, sending a lead code waveform to establish synchronous connection with a public safety answering point, and transmitting an audio compression frame obtained by encoding the minimum data set by using a vocoder through a wireless communication module. The method and the system support multiple operator networks and multiple network modes simultaneously, effectively overcome multipath fading and wireless interference, directly apply the vocoder EVRC-A or EVRC-B to the eCall system, and ensure that data transmission is completed within a specified time.
Description
Technical Field
The present application relates to the field of wireless communications technologies, and in particular, to a method, a system, and a medium for a multi-network and multi-mode vehicular emergency call.
Background
The eCall system is widely applied to in-vehicle emergency call services. When a vehicle is in collision, an eCall system vehicle-mounted emergency call device establishes an emergency call to an eCall rescue platform through a wireless network. The specification of the eCall system is specified In detail In the International Standard for Mobile communications (3 GPP TS 26.267 version 11.0.0 Release 11, eCall data transfer; In-band data solution; General description). This international standard for mobile communications also suggests the use of a standard codec, such as the vocoder GSM FR or the vocoder AMR, for encoding the modem output waveform, and specifies that a Minimum Data Set (MSD) should be successfully transmitted from the in-vehicle system IVS to the public safety answering point PSAP within 4 seconds.
Besides the two vocoders, many other vocoders have wide application in mobile communication systems, such as Enhanced Variable Rate Codec (EVRC), including vocoder EVRC-a and vocoder EVRC-B, which have low code Rate, high robustness and mature scheme, and most operators can support them by their base stations, but their coding principle is very different from that of vocoder FR and vocoder AMR, and if the vocoder EVRC-a or vocoder EVRC-B is directly applied to an eCall system, there are two main problems: firstly, Preamble waveforms (which are important references for synchronization of the eCall system) are difficult to detect successfully, so that the eCall system cannot be synchronized; secondly, the minimum data set can not be decoded in the specified time, and the rescue is delayed.
In addition, there are three operators in china, and the communication standards and the levels of network optimization supported by the operators are different, so that even in the same place, the signal quality and the corresponding call quality are different, and therefore, the alarm call of the common eCall system in some places cannot complete the transmission of MSD within a specified time, and rescue is delayed.
Disclosure of Invention
The method, the system and the medium for the multi-network multi-mode vehicle-mounted emergency call are mainly provided for solving the problems that in the prior art, an existing eCall system does not support multiple operators and multiple network modes, and when a vocoder EVRC-A or a vocoder EVRC-B is applied to the eCall system, a preamble waveform cannot be detected, a minimum data set cannot be decoded in time, and rescue is delayed.
In order to solve the above problems, the present application adopts a technical solution that: a multi-network multi-mode vehicle-mounted emergency call method is provided, which comprises the following steps:
when a vehicle has an accident, acquiring accident related information through a positioning module, wherein the accident related information comprises accident vehicle position information, accident occurrence time information and vehicle condition information, and generating a minimum data set from the accident related information;
according to the signal quality of the network, selecting one operator network with the highest signal quality from a plurality of operator networks as a current dial-up network, and selecting a network mode with the highest network quality from a plurality of network modes of the current dial-up network as a current network mode;
dialing an emergency call in a current network mode of a current dial-up network, sending a lead code waveform to establish synchronous connection with a public safety answering point, and transmitting an audio compression frame obtained by encoding a minimum data set by using a vocoder through a wireless communication module, wherein the vocoder comprises an enhanced variable rate codec and a standard codec provided by the international standard of mobile communication, and the dialing comprises automatic dialing or manual dialing;
and the public safety answering point receives the audio compression frame, demodulates the audio compression frame to obtain a minimum data set, and connects the emergency call to complete the call.
Another technical scheme adopted by the application is as follows: there is provided a multi-network multi-mode in-vehicle emergency call system, including:
the device comprises a module for acquiring accident related information through a positioning module when a vehicle has an accident, wherein the accident related information comprises accident vehicle position information, accident occurrence time information and vehicle condition information, and generating a minimum data set from the accident related information;
a module for selecting one operator network with highest signal quality from a plurality of operator networks as a current dial-up network according to the signal quality of the network, and selecting a network mode with highest network quality from a plurality of network modes of the current dial-up network as a current network mode;
the system comprises a wireless communication module, a module for dialing an emergency call, a module for sending a lead code waveform to establish synchronous connection with a public safety answering point and transmitting an audio compression frame obtained by encoding a minimum data set by a vocoder through the wireless communication module, wherein the vocoder comprises an enhanced variable rate codec and a standard codec provided by the international standard of mobile communication, and the dialing comprises automatic dialing or manual dialing;
and the module is used for receiving the audio compression frame by the public safety answering point, demodulating the audio compression frame to obtain a minimum data set, connecting the emergency call and completing the call.
Another technical scheme adopted by the application is as follows: there is provided a computer readable storage medium having stored thereon computer instructions operable to execute a multi-network multi-mode in-vehicle emergency call method in scenario one.
The technical scheme of the application can reach the beneficial effects that: the application designs a multi-network multi-mode vehicle-mounted emergency call method, a multi-network multi-mode vehicle-mounted emergency call system and a multi-network multi-mode vehicle-mounted emergency call medium. The method not only applies the vocoder EVRV-A or the vocoder EVRC-B to the operator network, but also supports multiple operator networks and multiple network modes, effectively overcomes multipath fading and wireless interference, and ensures the transmission success of the minimum data set; the method is simple to implement and can be supported only by simple software upgrading.
Drawings
In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to these drawings without inventive exercise.
Fig. 1 is a schematic diagram of an embodiment of a multi-network multi-mode vehicular emergency call method according to the present application;
FIG. 2 is a flow chart of the present application for placing an emergency call based on any one of the operator's networks;
FIG. 3 is a reference diagram of a Preamble waveform and its autocorrelation provided by the international mobile communications standard of the present application;
FIG. 4 is a diagram of the synchronization parameter Preamble waveform and its autocorrelation map updated by the vocoder EVRC-A applied in the present application;
FIG. 5 is a diagram of the synchronization parameter Preamble waveform and its autocorrelation map updated by the vocoder EVRC-B applied in the present application;
fig. 6 is a reference diagram of an IVS or PSAP modulated waveform and demodulated waveform provided by the international standard for mobile communications of the present application;
FIG. 7 is a diagram of modulation and demodulation waveforms for the application of vocoder EVRC-A update of the present application;
FIG. 8 is a diagram of a modulation waveform and a demodulation waveform of the present application employing vocoder EVRC-B update;
fig. 9 is a frame diagram of an implementation of a multi-network multi-mode vehicular emergency call method according to the present application;
fig. 10 is a schematic diagram of an embodiment of a multi-network and multi-mode vehicular emergency call system according to the present application.
With the above figures, there are shown specific embodiments of the present application, which will be described in more detail below. These drawings and written description are not intended to limit the scope of the inventive concepts in any manner, but rather to illustrate the inventive concepts to those skilled in the art by reference to specific embodiments.
Detailed Description
The following detailed description of the preferred embodiments of the present application, taken in conjunction with the accompanying drawings, will provide those skilled in the art with a better understanding of the advantages and features of the present application, and will make the scope of the present application more clear and definite.
It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.
The eCall system is widely applied to in-vehicle emergency call services. When a vehicle is in collision, an eCall system vehicle-mounted emergency call device establishes an emergency call to an eCall rescue platform through a wireless network. The european union stipulates that all new vehicles sold must have an eCall system installed before the end of 3 months in 2018. When an emergency occurs, the rescue service personnel can know the exact position at the fastest speed, so that the rescue service personnel can arrive at the scene of the traffic accident at the first time, and casualties caused in the road traffic accident are reduced to the maximum extent. At present, the keeping quantity and the production and sales quantity of automobiles are in the forefront of the world in China, and it is necessary to equip the automobiles with efficient eCall systems.
The method and the system optimize the existing eCall system, apply the EVRC series vocoder to the eCall system, and adopt various operator networks and network modes to ensure that information is timely sent and successfully decoded, and save lives of drivers and passengers in time.
The multi-network multi-mode vehicle-mounted emergency call method and the system can simultaneously support networks of multiple operators and multiple network modes, and can apply the vocoder EVRC-A and the vocoder EVRC-B to the eCall system to ensure that the MSD data can be sent in the specified time. The multi-network multi-mode vehicular emergency call method of the present application may also be applied to other vocoders based on the newer code excited linear predictive coding (RCELP), such as the EVRC series of vocoders EVRC-NW, the vocoder SMV, and the vocoder VMR-WB.
In the following, some terms in the present application are explained to facilitate understanding by those skilled in the art:
1. IVS: In-Vehicle System, Vehicle-mounted System;
2: PSAP: public Safety Answering Point, commonly called call center;
3: MSD: minimum Set of Data, wherein the message content of the Minimum Data Set may include location information, time, number of passengers, license plate number, and other information required for emergency rescue;
4: RSSI: received Signal Strength Indication;
5: preamble waveform: a preamble waveform, a series of signals transmitted before transmitting a desired signal. When the preamble signal is sent, an effective signal is sent immediately; the function of the device is to remind the receiving chip that a valid signal is about to be sent and pay attention to receiving so as to avoid losing the useful signal.
The following describes the technical solutions of the present application and how to solve the above technical problems with specific embodiments. The following several specific embodiments may be combined with each other, and details of the same or similar concepts or processes may not be repeated in some embodiments. Embodiments of the present application will be described below with reference to the accompanying drawings.
Fig. 1 shows an embodiment of a multi-network multi-mode vehicular emergency call method according to the present application.
In the embodiment shown in fig. 1, the multi-network multi-mode vehicular emergency call method mainly includes:
step S101, when a vehicle has an accident, accident related information is obtained through a positioning module, wherein the accident related information comprises accident vehicle position information, accident occurrence time information and vehicle condition information, and the accident related information is generated into a minimum data set.
In this embodiment, the positioning module installed in the vehicle may be a beidou or GPS or GNSS receiver, which is used to position the relevant information about the accident vehicle when the vehicle collides, including the position coordinates of the vehicle after the accident, the time of the accident, the damage degree of the accident vehicle, the casualties, and the like. In addition, the minimum data set is generated from the accident related information, the minimum data set is convenient to calculate by dialing a trigger source of action by dialing an emergency call, the generated minimum data set MSD does not exceed 140Byte, and the minimum data set MSD contains information such as vehicle position, driving direction, accident occurrence time, accident severity, vehicle identification, fuel category, number of passengers and the like. So that the rescue center knows the situation of the accident scene in more detail.
In a specific example of the application, when an accident of a vehicle is detected, a collision signal detected by a vehicle sensor is transmitted to a vehicle-mounted emergency call device through a bus, the vehicle-mounted emergency call device is triggered to automatically dial an emergency call, and a trigger source is marked as automatic trigger so as to calculate a minimum data set; or triggering the vehicle-mounted emergency call device to manually dial the emergency call through a key in the vehicle-mounted emergency call device, and marking the triggering source as manual triggering so as to calculate the minimum data set.
In this example, the manual trigger may cancel the dialing of the emergency call, and the automatic trigger may not cancel the dialing of the emergency call. When the vehicle is in serious condition, the detection device of the vehicle detects the damaged condition of the vehicle, and automatically triggers the automatic dialing of the emergency call to alarm, so that the lives of drivers and passengers are saved.
In the embodiment shown in fig. 1, the multi-network multi-mode vehicular emergency call method further includes:
step S102, according to the signal quality of the network, selecting one operator network with the highest signal quality from a plurality of operator networks as a current dial-up network, and selecting a network mode with the highest network quality from a plurality of network modes of the current dial-up network as a current network mode.
The implementation mode is the key content of the invention, and the multi-network multi-mode vehicle-mounted emergency call method can be compatible with networks of multiple operators, such as China Mobile and China Unicom. China telecom, and the like, and preferably selects the operator network with the highest network signal quality; in each operator's network, a plurality of network modes can be selected, and the preferred network mode is the network mode with the highest network quality; the success rate of sending the alarm information is highest in the network mode with the highest network quality of the operator network with the highest signal quality, and the help-seeking message can be preferentially sent out.
In a specific embodiment of the present application, dialing an emergency call in a current network mode of a current dial-up network, sending a preamble waveform to establish a synchronous connection with a public safety answering point, and transmitting an audio compressed frame obtained by encoding a minimum data set by a vocoder through a wireless communication module, further includes: and under the current network mode of the current dial-up network, if the transmission of the audio compression frame fails, returning the current network mode to another network mode of the current dial-up network according to the preset sequence of the network modes, redialing the emergency call, and transmitting the audio compression frame.
In this embodiment, each operator can support multiple network modes, such as 5G, 4G, 3G, and 2G, and when an emergency occurs and a network of one operator is selected as a dial-up network, the emergency call in each network mode is dialed according to a predetermined sequence of the network modes; when an emergency call is made based on a certain operator network, if a certain minimum data set (MSD) transmission fails, the mode falls back to the next network mode, for example, if the minimum data set (MSD) transmission fails to be sent based on the 3G network mode for the first time, the mode falls back to the 2G network mode for continuing to make the emergency call.
In a specific embodiment of the present application, dialing an emergency call in a current network mode of a current dial-up network, sending a preamble waveform to establish a synchronous connection with a public safety answering point, and transmitting an audio compressed frame obtained by encoding a minimum data set by a vocoder through a wireless communication module, further includes: if the audio compression frame transmission fails in all network modes of the current dialing network, automatically selecting another operator network as the current dialing network according to the preset sequence of the operator, re-dialing the emergency call in the new current dialing network according to the preset sequence of the network modes, and transmitting the audio compression frame until the audio compression frame transmission is successful or the electric quantity of the vehicle-mounted emergency call equipment is exhausted.
In this embodiment, at least two or more operator networks, such as china mobile, china telecom, and china Union, select the operator network with the best signal according to the signal quality (RSSI) before the emergency call is first dialed; and under all network modes of the network of the other operator, trying to dial emergency calls one by one and transmitting the audio compression frames, and switching the operators again until the transmission is successful and the transmission is failed. And continuing to transmit the audio compression frames according to the similar dialing mode until the audio compression frames are successfully transmitted or the vehicle-mounted emergency call equipment is completely charged.
Fig. 2 is a flow chart of the present application for making an emergency call based on any one of the carrier networks.
In the flow shown in fig. 2, an emergency call is dialed based on the highest network mode in any operator network, after dialing, the minimum data set is sent, and whether the minimum data set is sent successfully is judged, if so, the process is directly ended; if not, judging whether the signal falls back or not, if so, continuing to dial the emergency call and sending the minimum data set, and if not, directly ending.
In the embodiment shown in fig. 1, the multi-network multi-mode vehicular emergency call method further includes:
step S103, dialing the emergency call in the current network mode of the current dial network, sending a lead code waveform to establish synchronous connection with a public safety answering point, and transmitting an audio compression frame obtained by encoding the minimum data set by using a vocoder through a wireless communication module, wherein the vocoder comprises an enhanced variable rate codec and a standard codec provided by the international standard of mobile communication, and the dialing comprises automatic dialing or manual dialing.
The implementation mode is also the key content of the invention, and the application applies the enhanced variable rate codec to an eCall system to ensure that the minimum data set MSD can be sent within the specified time, so that the rescue center can quickly locate the accident vehicle and organize the rescue.
In a specific embodiment of the present application, the sending of the preamble waveform establishes a synchronous connection with the public safety answering point, and transmits an audio compressed frame obtained by encoding a minimum data set by using a vocoder through the wireless communication module, further comprising: when the minimum data set is coded by using an enhanced variable rate codec in the vocoder, updating a lead code waveform according to the type of the enhanced variable rate codec to obtain an updated lead code waveform, and establishing synchronous connection with a public safety answering point by using the updated lead code waveform; updating a pre-stored modulation waveform according to a system simulation function to obtain an updated modulation waveform, and modulating a minimum data set by using the updated modulation waveform to obtain an audio waveform; and coding the audio waveform through the enhanced variable-rate coder-decoder to obtain an audio compression frame, and transmitting the audio compression frame through the wireless communication module.
In the embodiment, the eCall system and the public safety answering point PSAP establish synchronous connection by updating the lead code waveform; the enhanced variable rate codec is applied to the eCall system by updating the modulation waveform, ensuring that the minimum data set MSD transmission is successful. The minimum data set is modulated by using the updated modulation waveform to obtain an audio waveform; recoding the audio waveform by calling another vocoder to obtain a recoded audio compression frame; and transmitting the audio compression frame through a wireless communication module corresponding to another vocoder. Each time the network mode is changed, the vocoder and the wireless communication module select a corresponding set, and re-encode and select a communication channel for transmission.
In the classic example, when activated, the eCall system provides notification information and associated location information to the most appropriate public safety answering point PSAP, transmits a notification defined by the standardized minimum data set MSD over the mobile wireless communication network, notifying that an accident has occurred and a response requiring emergency services is provided, and establishes a two-way audio call path between the occupants and the public safety answering point PSAP.
For example, there are two ways of dialing emergency call, manual and automatic, for example, when a car encounters a traffic accident, the driver and passengers CAN manually dial the emergency call to inform themselves of the location and related conditions, when the traffic accident is serious, the driver and passengers may not dial the call, if the car is equipped with an emergency call system, the emergency call system CAN manually dial the alarm call or automatically dial the alarm call, the trigger mechanism of the automatic alarm call is such that the emergency call system is connected to a bus (such as a CAN bus) of the car, when a sensor on the car detects the occurrence of a collision event, the emergency call system is triggered through the bus, and simultaneously the relevant information such as the geographic location and the like is also sent to the emergency call system, the emergency call system dials according to a pre-written dialing address, and simultaneously converts the relevant information such as the geographic location and the like into an audio waveform, and then the code is sent to a public safety answering point PSAP through a wireless communication module.
In a typical example, the present application supports three operator networks, china mobile, china unicom and chinese telecom, respectively; the system applies four wireless communication modules, namely a wireless communication module TD-SCDMA, a wireless communication module GSM, a wireless communication module WCDMA and a wireless communication module CDMA2000, and applies three vocoders, namely a vocoder AMR, a vocoder FR and a vocoder EVRC-A. For example, in a dial-up network of the chinese mobile, there are two encoding and transmission modes, one of which is encoding by the vocoder 1 as the vocoder AMR and transmitting by the corresponding wireless communication module 1 as the wireless communication module TD-SCDMA; the second is to perform coding by using the vocoder 2 as the vocoder FR, and to perform transmission for the wireless communication module GSM by using the corresponding wireless communication module 2. Under the dial-up network of China Unicom, there are two coding and transmission modes, one is that it is a vocoder AMR through the vocoder 1, the wireless communication module 3 is a wireless communication module WCDMA; the second is to perform coding by using the vocoder 2 as the vocoder FR, and to perform transmission for the wireless communication module GSM by using the corresponding wireless communication module 2. In the dial-up network of the chinese telecommunication, there is an encoding and transmission mode, which is to encode for the vocoder EVRC-a through the vocoder 3, and transmit for the wireless communication module CDMA2000 through the wireless communication module 4.
For example, china mobile is selected if its signal quality (RSSI indication) is better before the first emergency call is made. If the signal quality of the China Unicom is the best, under the 3G network mode, the step of dialing the emergency call is as follows: firstly, acquiring positioning information through a Beidou/GPS/GNSS receiver, and forming a minimum data set MSD according to a standard specification by adding relevant information of a vehicle; then inputting the minimum data set MSD into an IVS modem to obtain a modulation waveform; selecting vocoder 1 (AMR) to encode the minimum data set MSD into a standard AMR audio compression frame; transmitting the AMR audio compression frame to a Public Safety Answering Point (PSAP) through a wireless communication module 3 (WCDMA); if the transmission fails, the network mode of the operator network falls back to the 2G network and the above process is repeated based on the wireless communication module 2 (GSM) and vocoder 2 (FR); if the above steps are failed, repeating the above processes by using a wireless communication module 1 (TD-SCDMA) and a vocoder 1 (AMR) and a wireless communication module 2 (GSM) and a vocoder 2 (FR) of China Mobile; if the above-mentioned processes are failed, the vocoder 3 (EVRC-A) and wireless communication module 4 (CDMA 2000) of China telecom are used to encode and transmit information until the transmission is successful or the battery power of the vehicle-mounted emergency call device is exhausted.
In one embodiment of the present application, each operator network comprises at least one network mode, each operator network comprises at least one vocoder, and each vocoder corresponds to at least one wireless communication module. Under the condition of the same operator network, emergency calls need to be recoded when the emergency calls are dialed in a network mode, and a vocoder and a wireless communication module can be replaced.
In one embodiment of the present application, establishing a synchronous connection with a public safety answering point using an update preamble waveform comprises: and the public safety answering point receives the update lead code waveform and judges whether the update lead code waveform has an energy value and an autocorrelation value, wherein if the update lead code waveform is detected to have the energy value and the autocorrelation value, the synchronous connection between the public safety answering point and the accident vehicle is established.
In this embodiment, if the autocorrelation of the audio waveform of the preamble waveform cannot generate 5 autocorrelation values with equivalent energy and a large value after the preamble waveform is encoded and decoded by the vocoder EVRC-a or the vocoder EVRC-B, synchronization cannot be detected; the novel lead code waveform provided by the application can meet the synchronization condition.
In a specific embodiment of the present application, the updating the preamble waveform according to the type of the enhanced variable rate codec to obtain an updated preamble waveform further includes: obtaining an updating function according to a first system simulation function corresponding to a standard codec and a second system simulation function corresponding to an enhanced variable rate codec, wherein the values of the second system simulation functions corresponding to different types of enhanced variable rate codecs are different; and updating the pre-stored preamble waveform according to the updating function to obtain an updated preamble waveform, wherein the preamble waveform is provided by the international mobile communication standard and is pre-stored in the vehicle-mounted system or the public safety answering point in a table form.
In the embodiment, the updated lead code waveform can be obtained according to the system simulation function, and is pre-stored in the vehicle-mounted system or the public safety answering point in a table form, so that the lead code waveform can be directly read during use, and is quicker and more convenient.
In a specific embodiment of the present application, updating the preamble waveform to obtain an updated preamble waveform further includes: and adding a disturbing signal with energy smaller than a preset threshold value into the preamble waveform to obtain an updated preamble waveform, wherein the disturbing signal comprises a sine wave signal, a white noise signal or a pink noise signal.
In this embodiment, the effect of detecting synchronization of the updated preamble waveform obtained by simply adding the sine wave to the preamble waveform is the best.
Conventional vocoders, such as vocoder FR and vocoder AMR, attempt to match the shape of the original waveform during the encoding process, i.e. the shape of the waveform after the speech data is encoded and decoded by such codecs is close to the original waveform before encoding (although there is a slight difference), but the EVRC-series codec does not attempt to match the shape of the original waveform during the encoding process, but attempts to match the shape of the residual signal generated during the encoding process, although the sound quality is not degraded subjectively, the shape of the decoded waveform is greatly different from the original waveform, so that the autocorrelation value of the waveform after the Preamble waveform is encoded and decoded by the EVRC-series codec cannot satisfy the above-mentioned synchronization condition, i.e. 5 autocorrelation values with equivalent and large energy cannot be generated, and it is tested that adding a disturbance signal with small energy to the standard Preamble waveform can affect the amplitude of the original signal during the encoding process, the sine wave signal is found to have the best effect in signals such as sine waves, white noise, pink noise and the like through testing, and synchronization can be detected perfectly.
In a typical embodiment, a preamble waveform is assumed to be preamble (n), n is 0-1599, and a sine wave signal:
Sin(n) = Amp*sin(2*pi*f*ts)
where pi is pi, f is the frequency of the sine wave signal 800Hz, ts = n/fs, fs is the sampling rate 8000Hz, n = 0-1599, Amp is the signal amplitude (this value is small, a specific value is not disclosed here), and the new preamble waveform formed by adding the sine wave signal is:
Preamble(n) = Preamble(n) + Sin(n)，n=0~1599
the reference diagram of the Preamble waveform and the autocorrelation thereof provided by the international mobile communication standard of the application is shown in fig. 3, and it can be seen that, in the autocorrelation diagram, 5 autocorrelation values with relatively large amplitude are used, and when synchronization is detected, whether the 5 autocorrelation values with relatively large amplitude and relatively equivalent energy exist is detected, and the rest autocorrelation values are small; if not, it indicates that no synchronization signal is detected, and the eCall system cannot synchronize.
The synchronous parameter Preamble waveform updated by applying the vocoder EVRC-A or applying the vocoder EVRC-B and the autocorrelation graph thereof are respectively shown in FIG. 4 and FIG. 5; system synchronization can be detected using the vocoder EVRC-a or using the vocoder EVRC-B. The vocoder EVRC-A or the vocoder EVRC-B is applied, so that the shape of the waveform after being coded and decoded by the vocoder EVRC-A or the vocoder EVRC-B can not change greatly by utilizing the updated modulation waveform and the updated preamble waveform, and the successful demodulation is ensured.
In a specific embodiment of the present application, the updating a pre-stored modulation waveform according to a system simulation function to obtain an updated modulation waveform further includes: obtaining an updating function according to a first system simulation function corresponding to the standard codec and a second system simulation function corresponding to the enhanced variable rate codec, wherein the system simulation functions comprise a first system simulation function and a second system simulation function; and updating the prestored modulation waveform according to the updating function to obtain an updated modulation waveform, wherein the modulation waveform is provided by the international mobile communication standard and is prestored in the vehicle-mounted system in a table form.
In this embodiment, the update function may be obtained according to a ratio of the first system simulation function to the second system simulation function. Wherein, the types of the standard codec and the enhanced variable rate codec are different, and the specific values of the system simulation functions corresponding to the standard codec and the enhanced variable rate codec are also different, so that the values of the obtained update functions are also different.
In the classical example, the modulation waveform given by the international mobile communication standard 3GPP has a large change in the shape of the waveform after being coded and decoded by the enhanced variable rate codec EVRC, resulting in a high probability of failure in demodulation.
For example, assuming that the modulation waveform is Wav _ in, the vocoder FR or the vocoder AMR is regarded as a system, the corresponding first system simulation function is H1, and the modulation waveform is encoded and decoded by the vocoder FR or the vocoder AMR to obtain Wav _ out1, that is, Wav _ in × H1 = Wav _ out 1; regarding the enhanced variable rate codec EVRC as another system, wherein a corresponding second system simulation function is H2, and the modulated waveform is encoded and decoded by the enhanced variable rate codec EVRC to obtain Wav _ out2, that is, Wav _ in × H2 = Wav _ out 2; the object of the present application is that when the enhanced variable rate codec EVRC is used, the resulting waveform is close to Wav _ out1, then Wa _ in (H1/H2) H2 = Wav _ out 1; since the first system simulation function H1 and the second system simulation function H2 obtained in the simulation are approximate values, Wav _ out1 is also an approximate value, but this does not affect the correctness of the result of the modulation and demodulation. Wa _ in (H1/H2) is a new waveform, wherein the approximate values of the first system simulation function H1 and the second system simulation function H2 can be obtained by simulation, that is, given the input signal and the output signal, the system simulation function is obtained, which is a more mature technology.
Referring to fig. 6, it can be seen that the modulation waveform has 1 peak value and the demodulation waveform has 4 peak values, for example, the reference diagram of the modulation waveform and the demodulation waveform of the vehicle-mounted system IVS or the public safety answering point PSAP provided by the international mobile communication standard is shown; the modulation waveform and the demodulation waveform updated by the vocoder EVRC-A or the vocoder EVRC-B are respectively shown in fig. 7 and 8, and the waveforms coded and decoded by the method do not greatly differ from the shapes of the modulation waveform and the demodulation waveform provided by the international mobile communication standard.
In addition, the working mode of the vehicle-mounted system is that firstly, a minimum data set MSD is input; firstly, performing Cyclic Redundancy Check (CRC) operation; then, error correction coding is carried out through a forward error correction module H-ARQ Encoder; sending the Signal to a Modulator to modulate to generate an audio waveform, namely modulating the bit output in the previous step based on a modulation waveform specified by a standard according to a modulation method to generate the audio waveform; the modulation waveform is formulated by the international standard 3GPP for mobile communication, is prestored in the form of a table in the vehicle-mounted system IVS software, and can be read when in use. In order to work with the vocoder EVRC-A and the vocoder EVRC-B, the application provides a new modulation waveform, and the modulation waveform in the vehicle-mounted system IVS software can be replaced when the modulation waveform is specifically implemented.
The minimum data set MSD average transmission time is required to be less than 4 seconds when a vocoder EVRC-A and a vocoder EVRC-B are applied to an eCall system, the requirement of eCall system standard is met, and the effectiveness of the application can be obtained; in uplink transmission, synchronous detection, minimum data set detection and average transmission time meet requirements under the conditions of full code rate and variable code rate; the bit error rate can meet the requirement when the bit error rate is 0% and 5%.
The test result chart of the application of the vocoder EVRC-A and the vocoder EVRC-B to the eCall system is shown as the following section:
in the embodiment shown in fig. 1, the multi-network multi-mode vehicular emergency call method further includes:
and step S104, the public safety answering point receives the audio compression frame and demodulates the audio compression frame to obtain the minimum data set, and the emergency call is connected to complete the call.
In the embodiment, the audio compression frame is transmitted to the public safety answering point through the public telephone system, the public safety answering point demodulates the audio compression frame to obtain the minimum data set, and the emergency call is connected to complete the call. The public safety answering point receives the emergency call and automatically receives and decodes the data of the minimum data set MSD.
Note that the minimum data set MSD starts transmission after the eCall system is connected, earlier than voice telephony. I.e. the public safety answering point talks to the owner of the vehicle after receiving the minimum data set MSD. The public safety answering point may also require again the reception of a minimum data set MSD during voice telephony; during transmission of the minimum data set MSD, the phone is muted.
Fig. 9 is a block diagram of an implementation framework of a multi-network multi-mode vehicular emergency call method according to the present application.
In the frame diagram shown in fig. 9, the vehicle-mounted system IVS is located in a vehicle-mounted device, and can manually or automatically make an emergency call when an emergency occurs, and send key information of positioning coordinates such as beidou to a public safety answering point PSAP; the key module IVS modem of the vehicle-mounted system IVS comprises two processing directions, namely, a minimum data set MSD formed by input information from a Beidou receiver outputs a modulation waveform, and calls a vocoder to encode, and then sends out the modulation waveform through a voice channel; secondly, a signal from a public safety answering point PSAP is received through a voice channel, a vocoder is called for decoding, and the signal is input into an IVS modem to obtain a NACK or ACK signal of the public safety answering point PSAP. A Public Safety Answering Point (PSAP) answers the call of the vehicle-mounted system (IVS), acquires key information such as position and the like, and then dispatches rescue workers, wherein a key module PSAP modem of the PSAP comprises two processing directions, namely receiving a signal from the vehicle-mounted system (IVS) and demodulating and outputting a minimum data set (MSD) signal; and if the demodulation is successful, feeding back an ACK signal to the vehicle-mounted system IVS, otherwise, feeding back a NACK signal to the vehicle-mounted system IVS. The public land mobile network PLMN/public switched telephone network PSTN/general switched telephone network GSTN is a public telephone system through which the in-vehicle system IVS and public safety answering point PSAP complete a call.
Fig. 10 shows an embodiment of a multi-network multi-mode vehicular emergency call system according to the present application.
In the embodiment shown in fig. 10, the multi-network and multi-mode vehicular emergency call system mainly includes:
a module 1001, configured to obtain accident related information through a positioning module when an accident occurs in a vehicle, where the accident related information includes accident vehicle position information, accident occurrence time information, and vehicle condition information, and generate the accident related information into a module of a minimum data set;
a module 1002, configured to select, according to the signal quality of the network, an operator network with the highest signal quality from among multiple operator networks as a current dial-up network, and select, from among multiple network modes of the current dial-up network, a network mode with the highest network quality as a current network mode;
a module 1003, configured to dial an emergency call in a current network mode of a current dial-up network, send a preamble waveform to establish a synchronous connection with a public safety answering point, and transmit an audio compressed frame obtained by encoding a minimum data set using a vocoder through a wireless communication module, where the vocoder includes an enhanced variable rate codec and a standard codec provided by an international standard for mobile communication, and the dialing includes an automatic dialing or a manual dialing module;
a module 1004, configured to receive the audio compressed frame and demodulate the audio compressed frame by the public safety answering point to obtain a minimum data set, and connect the emergency call to complete the call.
In this embodiment, the car sensor detects a collision; transmitting the collision signal to a vehicle-mounted calling system through a bus to trigger the vehicle-mounted calling system to automatically dial a call; simultaneously transmitting the geographical position information to the vehicle-mounted calling system in a preset format (MSD format) through a bus; the vehicle-mounted calling system modulates the minimum data set MSD to generate an audio signal, then calls a vocoder to perform audio compression, and finally sends out the audio signal through a wireless communication module; and the PSAP receives the emergency call, automatically answers and decodes the minimum data set MSD data, and the call is ended.
The multi-network multi-mode vehicle-mounted emergency call system provided by the application can be used for executing the multi-network multi-mode vehicle-mounted emergency call method described in any of the above embodiments, and the implementation principle and the technical effect are similar, and are not described herein again.
In a specific embodiment of the present application, the functional modules in the multi-network multi-mode vehicular emergency call system of the present application may be directly in hardware, in a software module executed by a processor, or in a combination of both.
A software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the processor such the processor can read information from, and write information to, the storage medium.
The Processor may be a Central Processing Unit (CPU), other general-purpose Processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), a Field Programmable Gate Array (FPGA), other Programmable logic system, discrete Gate or transistor logic, discrete hardware components, or any combination thereof. A general purpose processor may be a microprocessor, but in the alternative, the processor may be any conventional processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing systems, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration. In the alternative, the storage medium may be integral to the processor. The processor and the storage medium may reside in an ASIC. The ASIC may reside in a user terminal. In the alternative, the processor and the storage medium may reside as discrete components in a user terminal.
In another embodiment of the present application, a computer readable storage medium stores computer instructions operable to perform a multi-network multi-mode vehicular emergency call method of any of the embodiments.
In the several embodiments provided in the present application, it should be understood that the disclosed system and method may be implemented in other ways. For example, the above-described system embodiments are merely illustrative, and for example, the division of the units is only one logical functional division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, systems or units, and may be in an electrical, mechanical or other form.
The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.
The above description is only an example of the present application and is not intended to limit the scope of the present application, and all equivalent structural changes made by using the contents of the specification and the drawings, which are directly or indirectly applied to other related technical fields, are included in the scope of the present application.
Claims (10)
1. A multi-network multi-mode vehicle-mounted emergency call method is characterized by comprising the following steps:
when a vehicle has an accident, acquiring accident related information through a positioning module, wherein the accident related information comprises accident vehicle position information, accident occurrence time information and vehicle condition information, and generating a minimum data set from the accident related information;
according to the signal quality of the network, selecting one operator network with the highest signal quality from a plurality of operator networks as a current dial-up network, and selecting a network mode with the highest network quality from a plurality of network modes of the current dial-up network as a current network mode;
dialing an emergency call in the current network mode of the current dial-up network, sending a lead code waveform to establish synchronous connection with a public safety answering point, and transmitting an audio compression frame obtained by encoding the minimum data set by using a vocoder through a wireless communication module, wherein the vocoder comprises an enhanced variable rate codec and a standard codec provided by the international standard of mobile communication, and the dialing comprises automatic dialing or manual dialing;
and the public safety answering point receives the audio compression frame, demodulates the audio compression frame to obtain the minimum data set, and connects the emergency call to complete the call.
2. The multi-network multi-mode vehicular emergency call method of claim 1, wherein the transmitting preamble waveform establishes a synchronous connection with a public safety answering point and transmits an audio compression frame encoded with the minimum data set by a vocoder through a wireless communication module, further comprising:
when the minimum data set is coded by using the enhanced variable rate coder-decoder in the vocoder, updating a lead code waveform according to the type of the enhanced variable rate coder-decoder to obtain an updated lead code waveform, and establishing synchronous connection with the public safety answering point by using the updated lead code waveform;
updating a pre-stored modulation waveform according to a system simulation function to obtain an updated modulation waveform, and modulating the minimum data set by using the updated modulation waveform to obtain an audio waveform;
and coding the audio waveform through an enhanced variable rate coder-decoder to obtain the audio compression frame, and transmitting the audio compression frame through the wireless communication module.
3. The multi-network multi-mode vehicular emergency call method of claim 1, wherein dialing an emergency call in a current network mode of the current dial-up network, sending a preamble waveform to establish a synchronous connection with a public safety answering point, and transmitting an audio compression frame encoded with the minimum data set by a vocoder through a wireless communication module, further comprising:
and under the current network mode of the current dial-up network, if the audio compression frame is failed to be transmitted, dropping the current network mode back to another network mode of the current dial-up network according to the preset sequence of the network modes, redialing the emergency call, and transmitting the audio compression frame.
4. The multi-network multi-mode vehicular emergency call method of claim 1, wherein dialing an emergency call in a current network mode of the current dial-up network, sending a preamble waveform to establish a synchronous connection with a public safety answering point, and transmitting an audio compression frame encoded with the minimum data set by a vocoder through a wireless communication module, further comprising:
if the audio compression frame transmission fails in all network modes of the current dialing network, automatically selecting another operator network as the current dialing network according to a preset sequence of an operator, redialing an emergency call according to the preset sequence of the network modes in a new current dialing network, and transmitting the audio compression frame until the audio compression frame transmission is successful or the electric quantity of the vehicle-mounted emergency call equipment is exhausted.
5. The multi-network multi-mode vehicular emergency call method according to claim 2, wherein the updating the pre-stored modulation waveform according to the system simulation function to obtain the updated modulation waveform, further comprises:
obtaining an updating function according to a first system simulation function corresponding to the standard codec and a second system simulation function corresponding to the enhanced variable rate codec, wherein the system simulation function comprises the first system simulation function and the second system simulation function;
and updating the prestored modulation waveform according to the updating function to obtain the updated modulation waveform, wherein the modulation waveform is provided by the international mobile communication standard and is prestored in the vehicle-mounted system in a table form.
6. The multi-network multi-mode vehicular emergency call method of claim 2, wherein the updating the preamble waveform according to the type of the enhanced variable rate codec to obtain an updated preamble waveform, further comprises:
obtaining an update function according to a first system simulation function corresponding to the standard codec and a second system simulation function corresponding to the enhanced variable rate codec, wherein the second system simulation functions corresponding to different types of the enhanced variable rate codecs have different values;
and updating the pre-stored preamble waveform according to the updating function to obtain the updated preamble waveform, wherein the preamble waveform is provided by international mobile communication standards and is pre-stored in a vehicle-mounted system or the public safety answering point in a table form.
7. The multi-network multi-mode vehicular emergency call method according to claim 2, wherein said establishing a synchronous connection with a public safety answering point using the updated preamble waveform comprises:
and the public safety answering point receives the update lead code waveform and judges whether the update lead code waveform has an energy value and an autocorrelation value, wherein if the update lead code waveform is detected to have the energy value and the autocorrelation value, the synchronous connection between the public safety answering point and the accident vehicle is established.
8. The multi-network multi-mode vehicular emergency call method of claim 2, wherein the updating the preamble waveform to obtain an updated preamble waveform further comprises:
adding a disturbing signal with energy smaller than a preset threshold value into the preamble waveform to obtain the updated preamble waveform, wherein the disturbing signal comprises a sine wave signal, a white noise signal or a pink noise signal.
9. A multi-network multi-mode vehicular emergency call system, comprising:
the device comprises a module, a positioning module and a data processing module, wherein the module is used for acquiring accident related information through the positioning module when a vehicle has an accident, and the accident related information comprises accident vehicle position information, accident occurrence time information and vehicle condition information and generating a minimum data set from the accident related information;
a module for selecting one operator network with highest signal quality from a plurality of operator networks as a current dial-up network according to the signal quality of the network, and selecting a network mode with highest network quality from a plurality of network modes of the current dial-up network as a current network mode;
the system comprises a wireless communication module, a module for dialing an emergency call in the current network mode of the current dial network, sending a lead code waveform to establish synchronous connection with a public safety answering point, and transmitting an audio compression frame obtained by encoding the minimum data set by using a vocoder through the wireless communication module, wherein the vocoder comprises an enhanced variable rate codec and a standard codec provided by the international standard of mobile communication, and the dialing comprises an automatic dialing module or a manual dialing module;
and the public safety answering point receives the audio compression frame, demodulates the audio compression frame to obtain the minimum data set, and connects the emergency telephone to complete the call.
10. A computer readable storage medium storing computer instructions operable to perform the multi-network multi-mode vehicular emergency call method of any of claims 1-8.
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Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101064655A (en) * | 2006-04-29 | 2007-10-31 | 阿尔卡特朗讯 | Method of providing a guest terminal with emergency access to a wlan |
| CN101390298A (en) * | 2005-09-28 | 2009-03-18 | Lg电子株式会社 | Method and apparatus for channel estimation |
| US9635530B2 (en) * | 2013-10-21 | 2017-04-25 | Intel IP Corporation | User equipment (UE) supporting packet-switched emergency calls over IP multimedia subsystem (IMS) |
| CN108074380A (en) * | 2016-11-11 | 2018-05-25 | 蒋林涛 | Car-mounted terminal, platform and vehicle safety safeguards system based on cellular communications network |
-
2021
- 2021-11-04 CN CN202111298022.7A patent/CN113747413B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101390298A (en) * | 2005-09-28 | 2009-03-18 | Lg电子株式会社 | Method and apparatus for channel estimation |
| US7684523B2 (en) * | 2005-09-28 | 2010-03-23 | Lg Electronics Inc. | Method and apparatus for channel estimation |
| CN101064655A (en) * | 2006-04-29 | 2007-10-31 | 阿尔卡特朗讯 | Method of providing a guest terminal with emergency access to a wlan |
| US9635530B2 (en) * | 2013-10-21 | 2017-04-25 | Intel IP Corporation | User equipment (UE) supporting packet-switched emergency calls over IP multimedia subsystem (IMS) |
| CN108074380A (en) * | 2016-11-11 | 2018-05-25 | 蒋林涛 | Car-mounted terminal, platform and vehicle safety safeguards system based on cellular communications network |
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