JPH0618645A - Gps receiver - Google Patents

Gps receiver

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Publication number
JPH0618645A
JPH0618645A JP17256192A JP17256192A JPH0618645A JP H0618645 A JPH0618645 A JP H0618645A JP 17256192 A JP17256192 A JP 17256192A JP 17256192 A JP17256192 A JP 17256192A JP H0618645 A JPH0618645 A JP H0618645A
Authority
JP
Japan
Prior art keywords
satellite
transmission time
gps
time
satellites
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP17256192A
Other languages
Japanese (ja)
Inventor
Yukari Fujiwara
ゆかり 藤原
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Japan Radio Co Ltd
Original Assignee
Japan Radio Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Japan Radio Co Ltd filed Critical Japan Radio Co Ltd
Priority to JP17256192A priority Critical patent/JPH0618645A/en
Publication of JPH0618645A publication Critical patent/JPH0618645A/en
Pending legal-status Critical Current

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  • Position Fixing By Use Of Radio Waves (AREA)

Abstract

PURPOSE:To initiate calculation of position measurement without waiting until the transmission times for all satellites needed for measuring position are obtained. CONSTITUTION:After a transmission time TSV1 and a position xs1, ys1 zs1 are calculated for a satellite SV1 out of GPS satellites used for measuring a position, a reception time Tu is calculated additionally utilizing an approximate position xu, yu, zu of a traveling body which is input from a user, etc. A position xsn, ysn, zsn is calculated based on past trajectory data for another GPS satellites SVn used for calculating position and a transmission time TSVn. is estimated from the GPS satellite SVn utilizing the position xsn, ysn, zsn, the approximate position xu, yu, zu of the traveling body, and the reception time Tu.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明は、GPS(Global Posit
ioning System )衛星からの航法データを復調して搭載
される移動体の測位を行うGPS受信機に関する。
BACKGROUND OF THE INVENTION The present invention relates to GPS (Global Position
ioning System) The present invention relates to a GPS receiver that demodulates navigation data from a satellite and performs positioning of a mobile body mounted on the GPS receiver.

【0002】[0002]

【従来の技術】GPSは、地球周回軌道上に打ち上げら
れている所定個数のGPS衛星から航法データを送信
し、地球上の移動体に搭載されているGPS受信機によ
りこのデータを受信して、当該移動体の測位を行うシス
テムである。このシステムでは、GPS衛星の位置及び
このGPS衛星と移動体の概略の距離(擬似距離)を求
めこれらに基づき所定のアルゴリズムによる測位計算を
行っている。GPS衛星の位置は、当該衛星から送信さ
れる軌道データを復調することにより得られ、GPS衛
星の擬似距離は、衛星からの電波の送信時刻からGPS
受信機のクロックによる受信時刻を減じて光速で除する
ことにより得られる。従って、測位計算を行うために
は、衛星からの送信時刻を正確に求める必要がある。
2. Description of the Related Art A GPS transmits navigation data from a predetermined number of GPS satellites launched in an orbit around the earth, and a GPS receiver mounted on a moving body on the earth receives this data, This is a system for positioning the moving body. In this system, the position of the GPS satellite and the approximate distance (pseudo distance) between the GPS satellite and the moving body are obtained, and the positioning calculation is performed by a predetermined algorithm based on these. The position of the GPS satellite is obtained by demodulating the orbit data transmitted from the satellite, and the pseudo range of the GPS satellite is calculated from the time when the radio wave from the satellite is transmitted.
It is obtained by subtracting the reception time by the receiver clock and dividing by the speed of light. Therefore, in order to perform the positioning calculation, it is necessary to accurately obtain the transmission time from the satellite.

【0003】図3には、一従来例に係るGPS受信機の
構成が示されている。この従来例は信号受信部1及びデ
ータ復調部2を備えており、GPS衛星から送信された
信号は信号受信部1によって受信され、さらにデータ復
調部2によって受信信号から航法データが復調される。
この航法データには、送信に係る衛星の軌道情報を示す
軌道データ(エフェメリスデータ)が含まれており、そ
の後段の測位計算部3は、この軌道データに基づき衛星
の位置を計算する。
FIG. 3 shows the configuration of a GPS receiver according to a conventional example. This conventional example includes a signal receiving unit 1 and a data demodulating unit 2. A signal transmitted from a GPS satellite is received by the signal receiving unit 1 and further the data demodulating unit 2 demodulates navigation data from the received signal.
This navigation data includes orbital data (ephemeris data) indicating the orbital information of the satellite to be transmitted, and the positioning calculation unit 3 at the subsequent stage calculates the position of the satellite based on this orbital data.

【0004】また、この測位計算を行う際、上に述べた
ように、衛星からの航法データの送信時刻を知る必要が
ある。衛星送信時刻計算部4は、この送信時刻を計算し
て測位計算部3に与える。送信時刻の計算は、20ms
単位時刻計算部5により得られる時刻と20ms以下時
刻計算部6により得られる時刻を加算することにより行
われる。
When performing this positioning calculation, it is necessary to know the time when the navigation data is transmitted from the satellite, as described above. The satellite transmission time calculation unit 4 calculates this transmission time and gives it to the positioning calculation unit 3. Calculation of transmission time is 20ms
It is performed by adding the time obtained by the unit time calculation unit 5 and the time obtained by the time calculation unit 6 of 20 ms or less.

【0005】まず、20ms単位時刻計算部5は、衛星
からの航法データの送信時刻を20msの分解能で求め
る。すなわち、衛星から送信される航法データは50ビ
ット/秒の伝送速度を有しており、データ復調部2によ
って復調したデータに基づき衛星からの航法データの送
信時刻を20msの分解能で求めることができる。ま
た、20ms以下時刻計算部6は、衛星からの航法デー
タの送信時刻を20ms以下の分解能で求める。GPS
衛星は、航法データをスペクトラム拡散して送信してお
り、GPS受信機においてこのスペクトラム拡散に係る
PNコード(擬似雑音コード)と同一のコードにより衛
星からの信号をスペクトラム逆拡散すれば、すなわち衛
星からの信号をベースバンドに変換してGPS受信機の
PNコードと位相同期させれば、当該PNコードの位相
情報から衛星からの送信時刻が20ms以下の分解能で
求められる。
First, the 20 ms unit time calculation unit 5 obtains the transmission time of navigation data from a satellite with a resolution of 20 ms. That is, the navigation data transmitted from the satellite has a transmission rate of 50 bits / second, and the transmission time of the navigation data from the satellite can be obtained with a resolution of 20 ms based on the data demodulated by the data demodulation unit 2. . Further, the time calculation unit 6 of 20 ms or less obtains the transmission time of the navigation data from the satellite with a resolution of 20 ms or less. GPS
The satellite transmits the navigation data by spread spectrum, and if the GPS receiver despreads the signal from the satellite with the same code as the PN code (pseudo noise code) related to the spread spectrum, that is, from the satellite. If the signal is converted to baseband and phase-synchronized with the PN code of the GPS receiver, the transmission time from the satellite can be obtained with a resolution of 20 ms or less from the phase information of the PN code.

【0006】測位計算部3は、このようにして求められ
た送信時刻に基づき衛星の擬似距離を求める。すなわ
ち、衛星送信時刻計算部4によって求められた送信時刻
と内蔵するクロックにより示される受信時刻との差を求
め、これを光速で除して擬似距離を求める。一方で、測
位計算部3は、この送信時刻における衛星の位置を前述
した軌道データに基づき計算する。従って、送信時刻が
正確にわかれば擬似距離、ひいては衛星位置を正確に求
めることができる。測位計算部3は、所定個数の衛星に
ついて位置及び擬似距離を求めた後、これらに基づき搭
載に係る移動体の位置を計算する。
The positioning calculator 3 calculates the pseudorange of the satellite based on the transmission time thus calculated. That is, the difference between the transmission time obtained by the satellite transmission time calculation unit 4 and the reception time indicated by the built-in clock is obtained, and this is divided by the speed of light to obtain the pseudo distance. On the other hand, the positioning calculation unit 3 calculates the position of the satellite at this transmission time based on the orbit data described above. Therefore, if the transmission time is accurately known, the pseudo range, and thus the satellite position, can be accurately determined. The positioning calculation unit 3 calculates the position and the pseudo-range of a predetermined number of satellites, and then calculates the position of the mobile body to be mounted based on these.

【0007】ここに、擬似距離が正確に衛星とGPS受
信機の距離を表しているならば、測位計算に使用する衛
星の個数は三次元測位であれば3個、二次元測位であれ
ば2個で足りる。しかし、実際にはGPS受信機のクロ
ックは誤差を有しており、擬似距離は衛星とGPS受信
機の距離(以下、区別するため伝搬距離という)に対し
てオフセットしている。従って、三次元測位には4個、
二次元測位には3個の衛星に係る位置及び擬似距離が必
要である。
If the pseudorange accurately represents the distance between the satellite and the GPS receiver, the number of satellites used for the positioning calculation is three for three-dimensional positioning and two for two-dimensional positioning. One is enough. However, in reality, the clock of the GPS receiver has an error, and the pseudorange is offset with respect to the distance between the satellite and the GPS receiver (hereinafter referred to as the propagation distance for distinction). Therefore, four for three-dimensional positioning,
Two-dimensional positioning requires the positions and pseudoranges of three satellites.

【0008】[0008]

【発明が解決しようとする課題】従来のGPS受信機に
おいては、測位計算に必要な個数の衛星全てについて位
置及び擬似距離が求められていなければ、測位計算を行
うことができなかった。すなわち、測位計算に必要な個
数の衛星について衛星からの航法データの復調が済んで
いない状況では、測位計算を行うことができなかった。
In the conventional GPS receiver, the positioning calculation cannot be performed unless the position and the pseudo range have been obtained for all the satellites required for the positioning calculation. That is, the positioning calculation could not be performed in a situation where the navigation data from the satellites have not been demodulated for the number of satellites required for the positioning calculation.

【0009】本発明は、このような問題点を解決するこ
とを課題としてなされたものであり、測位に必要な個数
の衛星についてデータが復調されるのを待つことなく測
位計算を行うことが可能なGPS受信機を提供すること
を目的とする。
The present invention has been made to solve the above problems, and it is possible to perform positioning calculation without waiting for data demodulation for the number of satellites required for positioning. The purpose of the present invention is to provide a GPS receiver.

【0010】[0010]

【課題を解決するための手段】このような目的を達成す
るために、本発明は、予め軌道データを収集格納してお
き、測位計算に使用するGPS衛星のうち少なくとも1
個について送信時刻及び位置が計算された段階で、求め
た位置及びユーザ等から入力される移動体の概略位置に
基づきこのGPS衛星から移動体までの電波伝搬距離を
求め、求められた電波伝搬距離及び送信時刻に基づき電
波の受信時刻を求め、測位計算に使用する他のGPS衛
星についてはその位置を収集格納済みの過去の軌道デー
タに基づき求め、求めた位置及び移動体の概略位置に基
づきこのGPS衛星から移動体までの電波伝搬距離を求
め、さらにこの電波伝搬距離及び先に求めた受信時刻に
基づき送信時刻が求められていないGPS衛星からの電
波の送信時刻を推定することを特徴とする。
In order to achieve such an object, the present invention collects and stores orbital data in advance and uses at least one of the GPS satellites used for positioning calculation.
At the stage when the transmission time and position of each piece were calculated, the radio wave propagation distance from this GPS satellite to the mobile body was calculated based on the calculated position and the approximate position of the mobile body input by the user, and the calculated radio wave propagation distance. And the reception time of the radio wave is calculated based on the transmission time, and the positions of other GPS satellites used for positioning calculation are calculated based on the past orbit data that has been collected and stored, and this position is calculated based on the calculated position and the approximate position of the moving body. A feature is that the radio wave propagation distance from the GPS satellite to the moving body is obtained, and the transmission time of the radio wave from the GPS satellite whose transmission time is not obtained is estimated based on the radio wave propagation distance and the previously obtained reception time. .

【0011】[0011]

【作用】本発明においては、測位計算に使用するGPS
衛星のうち少なくとも1個について送信時刻及び位置が
計算された後、この送信時刻、位置及びユーザ等から入
力される移動体の概略位置を利用して受信時刻が計算さ
れる。一方で、測位計算に使用する他のGPS衛星につ
いては過去の軌道データに基づきその位置が計算され、
この位置と上記移動体の概略位置及び受信時刻を利用し
てこのGPS衛星からの電波の送信時刻が推定される。
従って、少なくとも1個のGPS衛星について送信時刻
及び位置が求められた段階で、他のGPS衛星について
の航法データの復調、送信時刻の計算を待たずに測位計
算を開始可能となる。
In the present invention, the GPS used for positioning calculation
After the transmission time and the position of at least one of the satellites are calculated, the reception time is calculated by using the transmission time, the position and the approximate position of the mobile body input by the user or the like. On the other hand, the position of other GPS satellites used for positioning calculation is calculated based on past orbit data,
The transmission time of the radio wave from this GPS satellite is estimated using this position, the approximate position of the moving body, and the reception time.
Therefore, when the transmission time and the position of at least one GPS satellite are obtained, the positioning calculation can be started without waiting for the demodulation of the navigation data and the calculation of the transmission time of the other GPS satellites.

【0012】[0012]

【実施例】以下、本発明の好適な実施例について図面に
基づき説明する。なお、図3に示される従来例と同様の
構成には同一の符号を付し、説明を省略する。
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of the present invention will be described below with reference to the drawings. The same components as those of the conventional example shown in FIG. 3 are designated by the same reference numerals and the description thereof will be omitted.

【0013】図1には、本発明の一実施例に係るGPS
受信機の構成が示されている。この図に示されるよう
に、本実施例は、従来例の構成に衛星送信時刻推定部7
を付加した構成である。
FIG. 1 shows a GPS according to an embodiment of the present invention.
The configuration of the receiver is shown. As shown in this figure, the present embodiment is different from the conventional configuration in that the satellite transmission time estimation unit 7
Is added.

【0014】衛星送信時刻推定部7は、測位計算に必要
な個数の衛星についてのデータ復調を待たず、図2に示
される原理で他の衛星の送信時刻を推定する手段であ
る。このため、衛星送信時刻推定部7は、それまでに得
られている各衛星の軌道データを収集格納しておく。
The satellite transmission time estimation unit 7 is means for estimating the transmission times of other satellites according to the principle shown in FIG. 2 without waiting for data demodulation for the number of satellites required for positioning calculation. For this reason, the satellite transmission time estimation unit 7 collects and stores the orbital data of each satellite obtained up to that point.

【0015】本実施例の場合、まず、測位計算に用いる
衛星のうち1個目の衛星SV1について、衛星送信時刻
計算部4によって従来例と同様にして送信時刻TSV1
計算される。さらに、測位計算部3によって、この時刻
SV1 における衛星SV1の位置(xs1,ys1,zs1
が計算される。
In the case of the present embodiment, first, the satellite transmission time calculation unit 4 calculates the transmission time T SV1 for the first satellite SV1 of the satellites used for the positioning calculation in the same manner as in the conventional example. Further, the position of the satellite SV1 at this time T SV1 (x s1 , y s1 , z s1 ) is calculated by the positioning calculation unit 3.
Is calculated.

【0016】一方、衛星送信時刻推定部7には、移動体
の操縦者等により現在の移動体の概略位置(xu
u ,zu )が入力される。衛星SV1と移動体との間
の伝搬距離R1 は、測位計算部3によって求められるS
V1の位置(xs1,ys1,zs1)と入力される移動体の
概略位置(xu ,yu ,zu )を用いて計算することが
できる。すなわち、衛星送信時刻推定部7は、次の式に
より伝搬距離R1 を計算する。 R1 ={(xu −xs12 +(yu −ys12 +(zu −zs12 1/2 衛星送信時刻推定部7は、さらに、この伝搬距離R1
光速Cで除することにより、衛星SV1から移動体まで
の電波伝搬時間T1 を求める。すなわち、 T1 =R1 /C を求め、この伝搬時間T1 と先に求めた衛星SV1の送
信時刻TSV1 から次のように衛星SV1からの電波の受
信時刻Tu を計算する。 Tu =TSV1 +T1 衛星送信時刻推定部7は、このようにして受信時刻Tu
を計算する一方で、過去に収集格納した軌道データに基
づき測位計算に使用する他の2乃至3個のGPS衛星の
位置を計算する。今、当該他の2乃至3個のGPS衛星
のうちn番目の衛星SVnを例にとることとすると、衛
星送信時刻推定部7は、この衛星SVnの位置(xsn
sn,zsn)を過去に収集した軌道データに基づき計算
し、これを用いて現在の移動体との間の伝搬距離Rn
計算する。具体的には、 Rn ={(xu −xsn2 +(yu −ysn2 +(zu −zsn2 1/2 を計算する。さらに、衛星送信時刻推定部7は、 Tn =Rn /C を計算することにより、過去に収集した軌道データに基
づく衛星SVnの位置(xsn,ysn,zsn)から現在の
移動体の概略位置(xu ,yu ,zu )までの電波伝搬
時間Tn を計算する。
On the other hand, in the satellite transmission time estimation unit 7, the general position (x u ,
yu , zu ) is input. The propagation distance R 1 between the satellite SV1 and the moving body is S calculated by the positioning calculation unit 3.
It can be calculated by using the position (x s1 , y s1 , z s1 ) of V1 and the approximate position (x u , yu , z u ) of the input moving body. That is, the satellite transmission time estimation unit 7 calculates the propagation distance R 1 by the following formula. R 1 = {(x u -x s1) 2 + (y u -y s1) 2 + (z u -z s1) 2} 1/2 satellite transmission time estimating unit 7, further, the propagation distance R 1 By dividing by the speed of light C, the radio wave propagation time T 1 from the satellite SV1 to the moving body is obtained. That is, T 1 = R 1 / C is obtained, and the reception time T u of the radio wave from the satellite SV1 is calculated as follows from the propagation time T 1 and the transmission time T SV1 of the satellite SV1 previously obtained. T u = T SV1 + T 1 The satellite transmission time estimation unit 7 thus receives the reception time T u.
Meanwhile, the positions of the other two to three GPS satellites used for the positioning calculation are calculated based on the orbit data collected and stored in the past. Now, taking the n-th satellite SVn of the other two to three GPS satellites as an example, the satellite transmission time estimation unit 7 determines the position of the satellite SVn (x sn ,
y sn , z sn ) is calculated based on the orbit data collected in the past, and this is used to calculate the propagation distance R n with the current moving body. Specifically, calculating the R n = {(x u -x sn) 2 + (y u -y sn) 2 + (z u -z sn) 2} 1/2. Further, the satellite transmission time estimation unit 7 calculates T n = R n / C to calculate the current moving object from the position (x sn , y sn , z sn ) of the satellite SVn based on the orbit data collected in the past. The radio wave propagation time T n to the approximate position (x u , yu , z u ) is calculated.

【0017】このようにして受信時刻Tu 及び伝搬時間
n が得られると、衛星送信時刻推定部7は、次の式に
より衛星SVnからの送信時刻TSVn を推定する。
When the reception time T u and the propagation time T n are obtained in this way, the satellite transmission time estimation unit 7 estimates the transmission time T SVn from the satellite SVn by the following equation.

【0018】TSVn =Tu −Tn すなわち、前回の測位時点で得られ収集格納された軌道
データにより示される衛星SVnの位置(xsn,ysn
sn)は、厳密には現在の位置と異なったものである
が、後者は前者に対して大きく変化していないと見なす
ことができる。従って、この位置(xsn,ysn,zsn
から現在の移動体の概略位置(xu ,yu ,zu )まで
の電波伝搬時間Tn は、現在の衛星SVnの位置から現
在の移動体の概略位置(xu ,yu ,zu )までの電波
伝搬時間と概ね一致しているものと見なすことができ
る。本実施例においては、このような性格を有する伝搬
時間Tnを用いて推定送信時刻TSVn を計算している。
T SVn = T u −T n, that is, the position of satellite SVn (x sn , y sn , indicated by the orbit data acquired and stored at the previous positioning time).
z sn ) is strictly different from the current position, but the latter can be considered to have not changed significantly with respect to the former. Therefore, this position (x sn , y sn , z sn )
Approximate position of the current mobile from (x u, y u, z u) wave propagation time T n to the approximate position of the current mobile from the current position of the satellite SVn (x u, y u, z u ) It can be considered that the radio wave propagation time up to. In the present embodiment, the estimated transmission time T SVn is calculated using the propagation time T n having such characteristics.

【0019】さらに、推定送信時刻TSVn は、20ms
以下時刻計算部6の出力によって補正される。すなわ
ち、航法データの復調が済んでいない状態でも、PNコ
ードの位相同期(相関)による20ms以下の送信時刻
は得られることから、推定送信時刻TSVn と20ms以
下時刻計算部6の出力とを用いることにより、推定精度
をより高めることができる。
Further, the estimated transmission time T SVn is 20 ms.
Hereinafter, it is corrected by the output of the time calculation unit 6. That is, the estimated transmission time T SVn and the output of the time calculation unit 6 of 20 ms or less are used because the transmission time of 20 ms or less can be obtained due to the phase synchronization (correlation) of the PN code even when the navigation data has not been demodulated. As a result, the estimation accuracy can be further improved.

【0020】このように、測位に必要な3乃至4個の衛
星のうち1個(SV1)の送信時刻を計算し、これと入
力される移動体の概略位置(xu ,yu ,zu )を用い
て受信時刻Tu を計算した上で、他の2乃至3個の衛星
(SVn)の位置(xsn,ysn,zsn)を収集済みの軌
道データに基づき計算し、これに基づき伝搬時間Tn
求めて当該衛星の送信時刻TSVn を推定している。従っ
て、測位に必要な3乃至4個の衛星全てについて航法デ
ータの復調、送信時刻の計算を待たずに測位計算を行う
ことが可能になる。従って、いわゆるTTFF(Time T
o First Fix )が改善される。
In this way, the transmission time of one (SV1) of the three to four satellites necessary for positioning is calculated, and the approximate transmission position (x u , yu , z u ) of the mobile body that is input with this is calculated. ) Is used to calculate the reception time T u , and then the positions (x sn , y sn , z sn ) of the other two to three satellites (SVn) are calculated based on the collected orbit data, and Based on the propagation time T n , the transmission time T SVn of the satellite is estimated. Therefore, it becomes possible to perform the positioning calculation without waiting for the demodulation of the navigation data and the calculation of the transmission time for all the three to four satellites required for the positioning. Therefore, the so-called TTFF (Time T
o First Fix) is improved.

【0021】[0021]

【発明の効果】以上説明したように、本発明によれば、
軌道データを格納しておきこのデータを用いて送信時刻
を推定するようにしたため、少なくとも1個のGPS衛
星について送信時刻及び位置が求められた段階で、他の
GPS衛星についての航法データの復調、送信時刻の計
算を待たずに測位計算を開始可能となる。
As described above, according to the present invention,
Since the orbital data is stored and the transmission time is estimated using this data, when the transmission time and position for at least one GPS satellite are obtained, the navigation data for other GPS satellites are demodulated, Positioning calculation can be started without waiting for transmission time calculation.

【図面の簡単な説明】[Brief description of drawings]

【図1】本発明の一実施例に係るGPS受信機の構成を
示すブロック図である。
FIG. 1 is a block diagram showing a configuration of a GPS receiver according to an embodiment of the present invention.

【図2】この実施例における送信時刻推定原理を示す図
である。
FIG. 2 is a diagram showing a transmission time estimation principle in this embodiment.

【図3】一従来例に係るGPS受信機の構成を示すブロ
ック図である。
FIG. 3 is a block diagram showing a configuration of a GPS receiver according to a conventional example.

【符号の説明】[Explanation of symbols]

1 信号受信部 2 データ復調部 3 測位計算部 4 衛星送信時刻計算部 5 20ms単位時刻計算部 6 20ms以下時刻計算部 7 衛星送信時刻推定部 SV1 送信時刻が計算された衛星 SVn 送信時刻を推定する衛星 (xs1,ys1,zs1) 衛星SV1の位置 (xsn,ysn,zsn) 衛星SVnの位置 (xu ,yu ,zu ) 移動体の概略位置 R1 衛星SV1からの伝搬距離 Rn 衛星SVnからの伝搬距離 T1 衛星SV1からの伝搬時間 Tn 衛星SVnからの伝搬時間 Tu 衛星SV1からの受信時刻 TSV1 衛星SV1の送信時刻 TSVn 衛星SVnの推定送信時刻1 signal receiving unit 2 data demodulating unit 3 positioning calculating unit 4 satellite transmitting time calculating unit 5 20ms unit time calculating unit 6 20ms or less time calculating unit 7 satellite transmitting time estimating unit SV1 satellite where the transmitting time is calculated Estimate transmitting time satellite (x s1, y s1, z s1) position of the satellites SV1 (x sn, y sn, z sn) positions of satellites SVn (x u, y u, z u) from the approximate position R 1 satellites SV1 mobile propagation distance R n propagation distance T 1 estimated transmission time of the transmission time T SVn satellite SVn reception time T SV1 satellite SV1 from the propagation time T u satellites SV1 from the propagation time T n satellites SVn from satellite SV1 from satellite SVn

Claims (1)

【特許請求の範囲】[Claims] 【請求項1】 GPS衛星からの航法データを復調する
手段と、復調された航法データに基づきGPS衛星から
の電波の送信時刻を求める手段と、復調された航法デー
タに含まれGPS衛星の軌道を示す軌道データに基づき
当該送信時刻におけるGPS衛星の位置を求める手段
と、所定個数のGPS衛星からの送信時刻及び当該衛星
の位置に基づき測位計算を実行する手段と、を備え、移
動体に搭載されるGPS受信機において、 軌道データを収集格納する手段と、 移動体の概略位置を入力し、測位計算に使用するGPS
衛星のうち少なくとも1個について軌道データに基づき
求められた位置と入力される移動体の概略位置とに基づ
き当該GPS衛星から移動体までの電波伝搬距離を求
め、この電波伝搬距離と当該GPS衛星について求めら
れた送信時刻とに基づき電波の受信時刻を求める手段
と、 測位計算に使用するGPS衛星のうち送信時刻が求めら
れていないGPS衛星の位置を既に収集格納されている
過去の軌道データに基づき求め、求めた位置と前記入力
される移動体の概略位置とに基づき当該GPS衛星から
移動体までの電波伝搬距離を求め、この電波伝搬距離と
前記受信時刻とに基づき当該GPS衛星からの電波の送
信時刻を推定する手段と、 を備えることを特徴とするGPS受信機。
1. A means for demodulating navigation data from a GPS satellite, a means for obtaining a transmission time of a radio wave from the GPS satellite based on the demodulated navigation data, and a trajectory of the GPS satellite included in the demodulated navigation data. It is equipped with means for obtaining the position of the GPS satellite at the transmission time based on the orbit data shown, and means for performing positioning calculation based on the transmission time from a predetermined number of GPS satellites and the position of the satellite, and mounted on a mobile body. A GPS receiver that collects and stores orbital data and a GPS that is used for positioning calculation by inputting the approximate position of a moving body in a GPS receiver
For at least one of the satellites, the radio wave propagation distance from the GPS satellite to the mobile body is calculated based on the position obtained based on the orbital data and the approximate position of the mobile body to be input. Based on the means for obtaining the reception time of the radio wave based on the obtained transmission time, and the position of the GPS satellite for which the transmission time has not been obtained among the GPS satellites used for positioning calculation, based on the past orbit data already stored The radio wave propagation distance from the GPS satellite to the mobile body is obtained based on the obtained position and the input approximate position of the mobile body, and the radio wave from the GPS satellite is transmitted based on the radio wave propagation distance and the reception time. A GPS receiver comprising: means for estimating a transmission time.
JP17256192A 1992-06-30 1992-06-30 Gps receiver Pending JPH0618645A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP17256192A JPH0618645A (en) 1992-06-30 1992-06-30 Gps receiver

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP17256192A JPH0618645A (en) 1992-06-30 1992-06-30 Gps receiver

Publications (1)

Publication Number Publication Date
JPH0618645A true JPH0618645A (en) 1994-01-28

Family

ID=15944139

Family Applications (1)

Application Number Title Priority Date Filing Date
JP17256192A Pending JPH0618645A (en) 1992-06-30 1992-06-30 Gps receiver

Country Status (1)

Country Link
JP (1) JPH0618645A (en)

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010204057A (en) * 2009-03-06 2010-09-16 Casio Computer Co Ltd Gps receiving device and method of obtaining current time of the same
JP2013228345A (en) * 2012-04-27 2013-11-07 Japan Radio Co Ltd Satellite signal receiver
JP2014048289A (en) * 2012-08-31 2014-03-17 O2 Micro Inc Method and device for synchronizing navigation data
JP2014048286A (en) * 2012-08-31 2014-03-17 O2 Micro Inc Method and device for synchronizing navigation data
JP2014048288A (en) * 2012-08-31 2014-03-17 O2 Micro Inc Method and device for synchronizing navigation data
JP2014048287A (en) * 2012-08-31 2014-03-17 O2 Micro Inc Method and device for synchronizing navigation data
US9540975B2 (en) 2013-10-08 2017-01-10 Ge Jenbacher Gmbh & Co Og Oil mist separator

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2010204057A (en) * 2009-03-06 2010-09-16 Casio Computer Co Ltd Gps receiving device and method of obtaining current time of the same
JP2013228345A (en) * 2012-04-27 2013-11-07 Japan Radio Co Ltd Satellite signal receiver
JP2014048289A (en) * 2012-08-31 2014-03-17 O2 Micro Inc Method and device for synchronizing navigation data
JP2014048286A (en) * 2012-08-31 2014-03-17 O2 Micro Inc Method and device for synchronizing navigation data
JP2014048288A (en) * 2012-08-31 2014-03-17 O2 Micro Inc Method and device for synchronizing navigation data
JP2014048287A (en) * 2012-08-31 2014-03-17 O2 Micro Inc Method and device for synchronizing navigation data
US9540975B2 (en) 2013-10-08 2017-01-10 Ge Jenbacher Gmbh & Co Og Oil mist separator

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