CN111158029A - Adaptive variable search capture window length dynamic adjustment method for positioning equipment - Google Patents

Adaptive variable search capture window length dynamic adjustment method for positioning equipment Download PDF

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Publication number
CN111158029A
CN111158029A CN201811315978.1A CN201811315978A CN111158029A CN 111158029 A CN111158029 A CN 111158029A CN 201811315978 A CN201811315978 A CN 201811315978A CN 111158029 A CN111158029 A CN 111158029A
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positioning
gnss
current period
information
search
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CN201811315978.1A
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Chinese (zh)
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吴彤
唐陆军
刘超
肖登坤
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Beijing Jinkun Innovation Technology Co ltd
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Beijing Jinkun Innovation Technology Co ltd
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Priority to CN201811315978.1A priority Critical patent/CN111158029A/en
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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/13—Receivers
    • G01S19/24—Acquisition or tracking or demodulation of signals transmitted by the system
    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01S—RADIO DIRECTION-FINDING; RADIO NAVIGATION; DETERMINING DISTANCE OR VELOCITY BY USE OF RADIO WAVES; LOCATING OR PRESENCE-DETECTING BY USE OF THE REFLECTION OR RERADIATION OF RADIO WAVES; ANALOGOUS ARRANGEMENTS USING OTHER WAVES
    • G01S19/00—Satellite radio beacon positioning systems; Determining position, velocity or attitude using signals transmitted by such systems
    • G01S19/01—Satellite radio beacon positioning systems transmitting time-stamped messages, e.g. GPS [Global Positioning System], GLONASS [Global Orbiting Navigation Satellite System] or GALILEO
    • G01S19/13—Receivers
    • G01S19/35—Constructional details or hardware or software details of the signal processing chain
    • G01S19/37—Hardware or software details of the signal processing chain

Abstract

The invention relates to the field of satellite navigation positioning and multi-source fusion navigation positioning. A method for dynamically adjusting the length of an adaptive variable search acquisition window of a positioning device is characterized in that: and determining the initial search acquisition window length of the positioning equipment according to the number of visible satellites, the satellite carrier-to-noise ratio and the cold-start search acquisition time of a Global Navigation Satellite System (GNSS) module of the positioning equipment. Based on the satellite longitude and latitude acquisition result of the last positioning period, the number of visible satellites and the satellite carrier-to-noise ratio of the current period, other non-GNSS multi-source positioning auxiliary information which can be obtained by the equipment is automatically and dynamically adjusted to search and acquire the window length through fusion decision. The method can effectively improve the positioning performance of the positioning equipment based on the Global Navigation Satellite System (GNSS) in a complex environment, and can reduce the power consumption of the positioning equipment to achieve the aims of environmental protection and energy saving.

Description

Adaptive variable search capture window length dynamic adjustment method for positioning equipment
Technical Field
The invention belongs to the field of satellite navigation positioning and multi-source fusion navigation positioning.
Background
With the rapid development of indoor and outdoor navigation and positioning technologies and applications, various positioning devices are now on the market, including positioning bracelets, positioning wristwatches, smart phones, industrial intelligent positioning terminals, positioning trackers, and the like. The practical application requirements of these positioning terminals are increasingly pursuing high positioning accuracy, long standby time, and the need for miniaturization and wearability of the devices. The application of the common positioning equipment in outdoor open environment is relatively mature, such as an intelligent bracelet for recording running or walking, and the common positioning equipment integrates outdoor positioning and gait monitoring. However, the applicability and reliability in a complex environment are poor, particularly in urban canyons, overpasses, large business supermans, underground pipe galleries, highway railway tunnels, office areas and the like, the applicability of various positioning devices is poor at present, effective position information cannot be positioned frequently, and the power consumption of the devices is greatly consumed due to continuous searching of ephemeris information or other positioning information, so that the standby time of the devices is greatly shortened. Therefore, how to obtain a better performance compromise between positioning accuracy and power equipment consumption in a complex environment is an important problem of indoor and outdoor navigation positioning which needs to be solved urgently.
The invention relates to a dynamic adjustment method of a self-adaptive variable search capture window length of positioning equipment, which dynamically adjusts the search capture window length for positioning information calculation by self-adaptively sensing outdoor and indoor environments or other complex environments, not only can improve the positioning success rate and positioning accuracy in the complex environments, but also can save the power consumption of the positioning equipment in various scenes, thereby achieving better performance compromise of the positioning accuracy and the power equipment consumption.
Disclosure of Invention
A method for dynamically adjusting the length of a self-adaptive variable search capture window of a positioning device comprises the following core ideas:
determining the initial search acquisition window length of a Global Navigation Satellite System (GNSS) according to the number of visible satellites, the satellite carrier-to-noise ratio and the nominal cold start search acquisition time of a GNSS module of the positioning equipment; based on the satellite longitude and latitude acquisition result of the last positioning period, the number of visible satellites and the satellite carrier-to-noise ratio of the current period, other non-GNSS multi-source positioning auxiliary information which can be obtained by the equipment is automatically and dynamically adjusted to search and acquire the window length through fusion decision. Detecting whether the positioning equipment is reset or not, or the positioning state mode is changed; if the equipment reset or the positioning state mode is detected to be changed, resetting the initial search capture window length; and if the equipment reset or the positioning state mode change is not detected, the search capture window length is continuously adaptively and dynamically adjusted through fusion decision.
The initial search acquisition window length is defined as: initial acquisition search window length L0Is set to L0=N*TcoldWherein T iscoldSearching for capturing time for the nominal cold start of a GNSS module of the positioning equipment, wherein N is a positive integer and meets the condition that N is more than or equal to 1; the length of the initial acquisition search window is internally related to the number of visible satellites and the carrier-to-noise ratio of the satellites, is inversely proportional to the number of the visible satellites and the carrier-to-noise ratio of the satellites, and is directly reflected to a relation L0=N*TcoldThe value of N is equal to that of N; when the positioning device is in a state including, but not limited to, power on, reset, start charging, stop charging, from outdoor to indoor, from indoor to outdoor, etc., the positioning device resets the initial search acquisition window length.
For various complex environments, the length of a search capture window is adaptively and dynamically adjusted, and the method is mainly divided into the following four scenes:
scene one: if the effective GNSS latitude and longitude positioning information is obtained in the last positioning period, the positioning equipment can obtain other non-GNSS multi-information-source positioning auxiliary information. The solution is as follows: and adaptively reducing the search acquisition window length of the current period according to the number of visible satellites in the current period, the satellite carrier-to-noise ratio and other non-GNSS multi-source positioning auxiliary information available for the equipment.
Specifically, for scene one, if the last positioning cycle obtains effective GNSS longitude and latitude positioning information, and the positioning device can obtain at least one other non-GNSS multi-information-source positioning auxiliary information in the current cycle, it is assumed that the number of visible satellites in the current cycle is KsThe current period satellite carrier-to-noise ratio is gammasThe system presets the threshold value of satellite number as TH1The system presets the threshold value of satellite carrier-to-noise ratio as TH2And if the multi-source positioning auxiliary information of other non-GNSS is ξ, adaptively adjusting the length L of the search acquisition window in the current periodkComprises the following steps:
Lk=α1* L0
whereinα1Satisfies 0<α1<1, and α1=1/（γ1*（Ks/ TH1）+γ2*（Γs/ TH2）+γ3*ξ）
In the above formula, satisfy gamma1+γ2+γ3=1，0<γ1<1，0<γ2<1，0≤γ3<1, ξ is 0 or 1, if there is at least one other non-GNSS multi-source positioning assistance information, ξ =1, otherwise ξ = 0.
Scene two: if the effective GNSS latitude and longitude positioning information is obtained in the last positioning period, the positioning equipment cannot obtain other non-GNSS multi-source positioning auxiliary information. The solution is as follows: and adaptively reducing the search acquisition window length of the current period according to the number of visible satellites and the satellite carrier-to-noise ratio of the current period.
Specifically, for a second scene, if the last positioning period obtains effective GNSS longitude and latitude positioning information but the positioning device cannot obtain other non-GNSS multi-information-source positioning auxiliary information in the current period, the search capture window length L in the current period is adaptively adjustedkComprises the following steps:
Lk=α2* L0
α therein2Satisfies 0<α2<1，α2≥α1And α2=1/（γ1*（Ks/ TH1）+γ2*（Γs/ TH2））
In the above formula, satisfy gamma1+γ2=1，0<γ1<1，0<γ2<1。
Scene three: if the effective GNSS longitude and latitude positioning information cannot be obtained in the last positioning period, the number of visible satellites in the current period is smaller than or equal to a preset satellite number threshold value of the system, and the satellite carrier-to-noise ratio in the current period is smaller than or equal to a preset carrier-to-noise ratio threshold value of the system. The solution is as follows: the search acquisition window length of the current period is adaptively reduced.
Specifically, for scene three, if the effective GNSS longitude and latitude positioning information cannot be obtained in the last positioning period and the number of visible satellites in the current period is not availableKsLess than or equal to the preset satellite number threshold value TH of the system1And the satellite carrier-to-noise ratio of the current period is gammasLess than or equal to the preset carrier-to-noise ratio threshold value TH of the system2Adaptively adjusting the search capture window length L of the current periodkComprises the following steps:
Lk=β1* L0wherein β1Satisfies 0<β1<1。
Scene four: if the effective GNSS longitude and latitude positioning information cannot be obtained in the last positioning period, and the number of visible satellites and the satellite carrier-to-noise ratio in the current period are respectively larger than a preset threshold value of the system. The solution is as follows: the search capture window length of the current period is adaptively increased.
Specifically, for scene four, if the effective GNSS longitude and latitude positioning information cannot be obtained in the last positioning period and the number K of visible satellites in the current period is greater than the maximum valuesGreater than the preset satellite number threshold value TH of the system1And the satellite carrier-to-noise ratio of the current period is gammasGreater than the preset threshold value TH of carrier-to-noise ratio2Adaptively adjusting the search capture window length L of the current periodkComprises the following steps:
Lk=β2* L0wherein β2Satisfy β2≥1。
The invention is suitable for any indoor and outdoor positioning system, and for a Global Navigation Satellite System (GNSS), the GNSS comprises but is not limited to a Beidou positioning system, a global positioning system, a Russian glonass system and a European Galileo system; for non-GNSS multi-source positioning assistance information, the positioning assistance information includes, but is not limited to, cellular network wireless base station information, WIFI base station information, geomagnetic information, barometric information, bluetooth information, accelerometer information, gyroscope information, and the like.
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FIG. 1 is a schematic diagram of a method for dynamically adjusting the adaptive variable search acquisition window length of a positioning device
Detailed Description
Example 1:
according to the invention, assuming that the GNSS module of a certain positioning device has a nominal cold start search acquisition time of 40s, according to L0=N*TcoldSetting the initial search acquisition window length to 200s, i.e. N =5, L0=200 s. Meanwhile, the system presets the threshold value of the satellite number as TH1Set as 4, the system presets the satellite carrier-to-noise ratio threshold value as TH2Set to 10 dB. If scene one appears, according to the invention, the search capture window length can be adjusted to 40 s; if the scene two appears, the search capture window length can be adjusted to 80s according to the invention; if a scene three appears, according to the invention, the search capture window length can be adjusted to 60 s; if scene four occurs, the search acquisition window length can be adjusted to 300s according to the invention.

Claims (10)

1. A method for dynamically adjusting the length of an adaptive variable search acquisition window of a positioning device is characterized in that:
determining the initial search acquisition window length of a Global Navigation Satellite System (GNSS) according to the number of visible satellites, the satellite carrier-to-noise ratio and the nominal cold start search acquisition time of a GNSS module of the positioning equipment;
based on the satellite longitude and latitude acquisition result of the last positioning period, the number of visible satellites and the satellite carrier-to-noise ratio of the current period, other non-GNSS multi-source positioning auxiliary information which can be obtained by the equipment is automatically and dynamically adjusted to search and acquire the window length through fusion decision.
2. Detecting whether the positioning equipment is reset or not, or the positioning state mode is changed; if the equipment reset or the positioning state mode is detected to be changed, resetting the initial search capture window length; and if the equipment reset or the positioning state mode change is not detected, the search capture window length is continuously adaptively and dynamically adjusted through fusion decision.
3. The adaptive dynamic adjustment search acquisition window length of claim 1, wherein:
if the effective GNSS longitude and latitude positioning information is obtained in the last positioning period and the positioning equipment can obtain the multi-source positioning auxiliary information of other non-GNSS, the search capture window length in the current period is reduced in a self-adaptive manner according to the number of visible satellites in the current period, the satellite carrier-to-noise ratio and the other non-GNSS multi-source positioning auxiliary information which can be obtained by the equipment;
if the effective GNSS longitude and latitude positioning information is obtained in the last positioning period, but the positioning equipment cannot obtain multi-source positioning auxiliary information of other non-GNSS, the search capture window length in the current period is reduced in a self-adaptive manner according to the number of visible satellites and the satellite carrier-to-noise ratio in the current period;
if the effective GNSS longitude and latitude positioning information cannot be obtained in the last positioning period, the number of visible satellites in the current period is smaller than or equal to a preset satellite number threshold value of the system, and the satellite carrier-to-noise ratio in the current period is smaller than or equal to a preset carrier-to-noise ratio threshold value of the system, the search capture window length in the current period is reduced in a self-adaptive mode;
and if the effective GNSS longitude and latitude positioning information cannot be obtained in the last positioning period, and the number of visible satellites and the satellite carrier-to-noise ratio in the current period are respectively greater than a preset threshold value of the system, adaptively increasing the length of a search capture window in the current period.
4. The initial search acquisition window length of claim 1, wherein:
initial acquisition search window length L0Is set to L0=N*TcoldWherein T iscoldSearching for capturing time for the nominal cold start of a GNSS module of the positioning equipment, wherein N is a positive integer and meets the condition that N is more than or equal to 1;
the length of the initial acquisition search window is internally related to the number of visible satellites and the carrier-to-noise ratio of the satellites, is inversely proportional to the number of the visible satellites and the carrier-to-noise ratio of the satellites, and is directly reflected to a relation L0=N*TcoldThe value of N is equal to that of N;
when the positioning device is in a state including, but not limited to, power on, reset, start charging, stop charging, from outdoor to indoor, from indoor to outdoor, etc., the positioning device resets the initial search acquisition window length.
5. The adaptive current period search acquisition window length reduction according to claim 1 and claim 2, wherein:
if the last positioning cycle obtains valid GNSS longitude and latitude positioning information, and the positioning equipment can obtain at least one other non-GNSS multi-information-source positioning auxiliary information in the current period, and the number of visible satellites in the current period is assumed to be KsThe current period satellite carrier-to-noise ratio is gammasThe system presets the threshold value of satellite number as TH1The system presets the threshold value of satellite carrier-to-noise ratio as TH2And if the multi-source positioning auxiliary information of other non-GNSS is ξ, adaptively adjusting the length L of the search acquisition window in the current periodkComprises the following steps:
Lk=α1* L0
α therein1Satisfies 0<α1<1, and α1=1/（γ1*（Ks/ TH1）+γ2*（Γs/ TH2）+γ3*ξ）
In the above formula, satisfy gamma1+γ2+γ3=1，0<γ1<1，0<γ2<1，0≤γ3<1, ξ is 0 or 1, if there is at least one other non-GNSS multi-source positioning assistance information, ξ =1, otherwise ξ = 0.
6. The adaptive current period search acquisition window length reduction according to claim 1 and claim 2, wherein:
if the effective GNSS longitude and latitude positioning information is obtained in the last positioning period, but the positioning equipment cannot obtain the multi-source positioning auxiliary information of other non-GNSS in the current period, the search capture window length L in the current period is adjusted in a self-adaptive mannerkComprises the following steps:
Lk=α2* L0
α therein2Satisfies 0<α2<1，α2≥α1And α2=1/（γ1*（Ks/ TH1）+γ2*（Γs/ TH2））
In the above formula, satisfy gamma1+γ2=1，0<γ1<1，0<γ2<1。
7. The adaptive current period search acquisition window length reduction according to claim 1 and claim 2, wherein:
if the effective GNSS longitude and latitude positioning information cannot be obtained in the last positioning period and the visible satellite number K of the current periodsLess than or equal to the preset satellite number threshold value TH of the system1And the satellite carrier-to-noise ratio of the current period is gammasLess than or equal to the preset carrier-to-noise ratio threshold value TH of the system2Adaptively adjusting the search capture window length L of the current periodkComprises the following steps:
Lk=β1* L0
β therein1Satisfies 0<β1<1。
8. The method of claim 1 and claim 2, wherein adaptively increasing the current period search acquisition window length comprises:
if the effective GNSS longitude and latitude positioning information cannot be obtained in the last positioning period and the visible satellite number K of the current periodsGreater than the preset satellite number threshold value TH of the system1And the satellite carrier-to-noise ratio of the current period is gammasGreater than the preset threshold value TH of carrier-to-noise ratio2Adaptively adjusting the search capture window length L of the current periodkComprises the following steps:
Lk=β2* L0
β therein2Satisfy β2≥1。
9. The Global Navigation Satellite System (GNSS) of claim 1, wherein:
including but not limited to the beidou positioning system, the global positioning system, the russian glonass system, the european galileo system.
10. It is non-GNSS multi-source positioning assistance information as claimed in claim 1 and claim 2, characterized by:
the method includes but is not limited to non-GNSS multi-source positioning auxiliary information such as cellular network wireless base station information, WIFI base station information, geomagnetic information, barometric information, Bluetooth information, accelerometer information, gyroscope information and the like.
CN201811315978.1A 2018-11-07 2018-11-07 Adaptive variable search capture window length dynamic adjustment method for positioning equipment Pending CN111158029A (en)

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