1306952 九、發明說明： 【發明所屬之技術領域】 本發明係關於一種定位方法，尤指一種應用於無線電系 統之定位方法。 【先前技術】 現行許多自動定位方法都是利用三角定位法先測量待測 點與二個以上已知位置的參考點之間的距離或角度，來計 算得知待測點的位置。測量距離的方法亦有許多種，其中 利用無線電信號的特性是最為方便的測量方法。例如，第 一種方法即是利用無線電波行進速度恆定的特性，測量從 發射源到達接收點的電波傳遞時間再換算成距離，使用此 種方式的代表即為GPS衛星定位系統。雖然這種方法在目 月'J最為方便且最為風行，但是待測點與衛星之間不能有障 礙物’因此無法在室内使用、容易有死角而且設備較貴。 另一種方法則是利用無線電電波強度換算成信號行經距離 來進行定位的方法。因為無線電信號的強度自發射源發射 後會隨著行經的距離增加而衰減，在沒有障礙物與反射物 的理想情形下’無線電信號強度之衰減會與距離維持一穩 定的數學關係。換言之，比較信號的發射強度與接收點的 強度即可反推發射源與接收點的距離。 由於目前很多現代化地區有已經佈有無線電網路，例 如：無線區域網路（WLAN)，所以可直接利用無線電網路的 信號衰減來測量距離β請參閱圖1，圖1係為習知利用無線 區域網路之定位方法的示意圖。如圖1所示’ 一旦藉由無線 116254.doc 1306952 電信號衰減推知3個發射器與待測位置間的距離為^ 们’便可以㈣地利用三點定位的方式^位待测位置卜然 而，如圖2所示，在實際操作上無線電信號從發射器發出^ 後到達待測位置y所走的路徑不m線，如此一來^ 使用上述定位方法便會造成一定的誤差。 有鑑於此’目前極有必要發展-種不會大幅增加運算複 雜度又可提高定位精確的的方法。 【發明内容】 本發明之-目的在於提供-種決定—發射ϋ之-幻影位 置的方法。 ” 本發明之另一目的在於提供一種幻影定位方法以在不大 幅增加運算複雜度的情形下提高定位的精確度。 本發明之-實施例係提供一種決定一發射器之幻影位置 之方法’其包含下列之步驟：選擇該發射器週遭的複數個 備選幻影位置；選擇一特定區域中的一樞軸位置與一待測 位置；測量該枢軸位置與該待測位置之無線電信號強度； 依據該待測位置以及該樞轴位置之無線電信號強度、該梅 軸位置及該待測位置推導出該等備選幻影位置中每一者所 ^應的距離錯誤率；及選擇具有最小距離錯誤率的備選幻 衫位置作為該發射器對應於該特定區域的幻影位置。 本發明之另一實施例提供一種應用於-無線電系統的定 位方法’該無線電系統包含至少三個發射器，該方法包含 下列步驟：決定該等發射器之各幻影位置；測量-待測位 置相對應於該各發射器之無線電信號強度；依據該等無線 116254.doc ί3〇69$2 ::號強度決定該等幻影位置與該待測 依據該等咖W叫置及 依據本發明所提供的實施例，在定位計算 ㈣發射n所取代’在不大幅增加工作量及 == 下，定位之精確度可提升12。/。至20%。 一 ]月形 【實施方式】 ^ 技財由無線電波訊號強度測量到的距離 :非發射器到待測位置的直線距離之問題，本發明欲為每 個用來定位的發射器找出一相對應的约影位置，使幻影位 置與待測位置間的距離恰等於無線電信號從發射器到待測 位置的行經距離。 4=閱圖3,圖3係為本發明幻影定位方法之一較佳實施例 的7^意圖°如圖3所示’在最佳狀況下’無線電信號發射器 ΑΡΐ、ΑΡ2、Αί>3到待測位置y的行經距離恰等於從幻影位置 到待測位置y的直線距離（亦即dr、d2,、d3，p因此，本發 月所揭露的幻影定位方法之一實施例，包含下列步驟：利 用上述方法決定發射器AP!、AP2、AP3的幻影位置AP〆、 AP2、AP3’ ；測量待測位置y相對應於該各發射器之無線電 6號強度；依據無線電信號強度決定幻影位置APi,、aj>2,、 AP’與待測位置y間的距離以，、d2,、d3,；以及利用三點定 位的方式依據距離dl，、d2,、d3，以及幻影位置AIV、AP〆、 AIV來定位待測位置7。 清參閱圈4 ’圖4係為本發明中決定一發射器之幻影位置 之方法的一較佳實施例之示意圖。雖然在實施幻影定位方 116254.doc 13069521306952 IX. Description of the invention: [Technical field to which the invention pertains] The present invention relates to a positioning method, and more particularly to a positioning method applied to a radio system. [Prior Art] Many current automatic positioning methods use the triangulation method to first measure the distance or angle between the point to be measured and the reference point of two or more known positions to calculate the position of the point to be measured. There are also many methods for measuring the distance, and the use of the characteristics of the radio signal is the most convenient measurement method. For example, the first method uses the characteristic that the traveling speed of the radio wave is constant, and measures the radio wave transmission time from the transmitting source to the receiving point and converts it into a distance. The representative of this method is the GPS satellite positioning system. Although this method is the most convenient and popular in the month, there is no obstacle between the point to be measured and the satellite. Therefore, it cannot be used indoors, it is easy to have dead ends and the equipment is expensive. Another method is to use the radio wave intensity to be converted into a signal travel distance for positioning. Since the intensity of the radio signal is attenuated as the distance traveled from the source, the attenuation of the radio signal strength maintains a stable mathematical relationship with the distance in the absence of obstacles and reflectors. In other words, comparing the emission intensity of the signal with the intensity of the receiving point, the distance between the transmitting source and the receiving point can be reversed. Since many modern areas have been equipped with radio networks, such as wireless local area networks (WLANs), the distance attenuation can be directly measured by the signal attenuation of the radio network. Please refer to Figure 1, which is a conventional use of wireless. Schematic diagram of the location method of the local area network. As shown in Figure 1 ' Once the distance between the three transmitters and the position to be tested is inferred by the wireless 116254.doc 1306952 electrical signal attenuation, we can use the three-point positioning method to determine the position. As shown in FIG. 2, in the actual operation, the path taken by the radio signal from the transmitter to the position to be tested y is not m-line, and thus the use of the above positioning method may cause a certain error. In view of this, it is extremely necessary to develop a method that does not significantly increase the computational complexity and can improve the positioning accuracy. SUMMARY OF THE INVENTION It is an object of the present invention to provide a method for determining the position of the ϋ- phantom. Another object of the present invention is to provide a phantom positioning method for improving the accuracy of positioning without greatly increasing the computational complexity. Embodiments of the present invention provide a method of determining the phantom position of a transmitter. The method comprises the steps of: selecting a plurality of alternative phantom positions around the transmitter; selecting a pivot position and a position to be tested in a specific area; measuring the radio signal strength of the pivot position and the position to be tested; The position to be tested and the radio signal strength of the pivot position, the position of the beam axis, and the position to be tested derive a distance error rate for each of the candidate phantom positions; and selecting a minimum distance error rate The alternative hood position is used as the phantom position of the transmitter corresponding to the particular area. Another embodiment of the invention provides a method of locating an application-radio system comprising at least three transmitters, the method comprising the following Step: determining the phantom positions of the transmitters; measuring - the location to be measured corresponds to the radio of the transmitters Strength of the number; according to the wireless 116254.doc ί3〇69$2:: intensity, the phantom position is determined according to the embodiment according to the invention, and the positioning calculation is performed according to the embodiment of the invention. Replaced by 'without a large increase in workload and ==, the accuracy of positioning can be increased by 12% to 20%. One] Moon shape [Implementation] ^ The distance measured by radio wave signal strength: Non- The problem of the linear distance from the transmitter to the position to be tested, the present invention intends to find a corresponding shadow position for each transmitter used for positioning, so that the distance between the phantom position and the position to be measured is exactly equal to the radio signal from the emission. The distance traveled by the device to the position to be tested. 4 = See Figure 3, which is a preferred embodiment of the phantom positioning method of the present invention. Figure 7 shows the 'in the best case' radio signal transmission as shown in Figure 3. The distance traveled by ΑΡΐ, ΑΡ2, Αί>3 to the position to be tested y is exactly equal to the linear distance from the phantom position to the position y to be tested (ie, dr, d2, d3, p, therefore, the phantom positioning disclosed in this month) An embodiment of the method comprises the following steps: The phantom positions AP〆, AP2, and AP3' of the transmitters AP!, AP2, and AP3 are determined by the above method; the measured position y corresponds to the radio 6 intensity of the transmitters; the phantom position APi is determined according to the radio signal strength, , aj>2, the distance between the AP' and the position to be tested y, d2, d3, and the three-point positioning method according to the distances dl, d2, and d3, and the phantom positions AIV, AP〆, AIV to locate the position to be tested 7. Clear reference circle 4 ' Figure 4 is a schematic diagram of a preferred embodiment of the method for determining the phantom position of a transmitter in the present invention. Although the phantom positioning method is implemented 116254.doc 1306952
=至少須找出三個發射器的幻影位置才可進行定位，但 =:例中僅以尋找發射器Αρι的幻影位置Μ、例，替發 另：、2 AP3尋找幻影位置的方法與發射器Ap丨相同，故不 .述。依據本實施例，线幻影位置之方法包含以下井 驟針對特疋區域，例如：一間教室的範圍’決定出用 於定位的發射器ΑΡι;冑靠近發射器Μ的教室門口或窗 戶或其他可供無線電信號輕易通過的地點選擇為 位置pv’並且於特定區域内選擇一已知位置χ;在發射;J Α已 =決定Γ個備選幻影位置ΡΡ;測量樞轴位置PV與 X之…、線電信號強度；依據公式争=&($)”推導出已 知位置χ相對於發射器AP1之距離dx，其中sx、s〜別為已 。置及樞軸位置之信號強度，dv為柩轴位置相對於發射 器AP,之距離’且8^皆為已知參數；將推導出二距 離d X與已知位置到每一備選幻影位置間距離的差值分別除 以已知位置X到發射器ΑΡι的實際距離，以得到每—備選幻 影位置所對應的距離錯誤率；最後，選擇具有最小距離錯 誤率的備選幻影位置作為發射器ΑΡι於特定區域的幻影位 置 AIV。 明/主忍，公式| =哈”係為習知利用6知信號強度之比值 與一已知距離求得一未知距離的方式，係數]^與11的決定會 隨外界環境有所改變，學界亦有許多分析係數…的研究 結果，因此決定係數1^與11的方法並非本發明之重點，並且 本發明也可利用其他功能相近之習知公式來藉由信號強度 求得已知位置X相對於發射器ΑΡι之距離叔而不以上述實施 116254.doc 1306952 例為限。 此外，上述實施例係在一特定區域内僅僅利用一個已知 位置找出發射II ΑΡι的幻影位置Ap】，，之後若特定區域内的 4何個待测點進行定位時都可利用相同的幻影位置API, 〆、行疋位以降低计舁複雜度。換言之，如果必須對每個 待測點都找出相對應的幻影位置時，則會產生過大的工作 量而不切實際。 …、而，如果必須進一步提高幻影位置的準確度，則可依 據本發明之另一較佳實施例，在上述特定區域内取數個不 同的已知位置共用同一個柩轴位置，來針對每一個備選幻 影位置產生數個距離錯誤率以取其平均，並且選擇且有最 小平均距離錯誤率的備選幻影位置為幻影位置。雖然本實 ==用數個不同的已知位置找出幻影位置的方法工作 實施例略高’但其亦伴隨有精確度較高的優點。 再者，依據本發明之又另—較佳實施例，上述 域更可以劃分成複數個子特定區域，這種情形下，每疋= =定區_決定的幻影位置AP1，、碼t、AP3，可能不 AP’，但疋子特定區域的面積越小，將所得到的幻影位置 1 AI>2、AP3’用於定位的可靠度也越高。 前述之幻影定位方法或是決定幻影位置之 腦程式指令完成。該等電腦程式指 電 可程式化之資料處理裝置，以執行幻影他 幻影位置之方法。該等電腦程式指令亦可儲存== 取之记錄媒體（如磁帶，磁片，光碟， ' 可凟 八更碟，Ic記憶體等記 116254.doc 1306952 錄媒體），以供後續載入電腦中使用。 依據本表月所提供的實施例，在定位計算中實際發射器係被 幻影發射器所取代，如此一來可以在不大幅增加工作量及運算 複雜度的情形下，使定位之精確度提升12%至2〇%。 雖然本發明之技術內容與特徵係如上所述，然於本發明 之技術領域具有通常知識者仍可在不脖離本發明之教導盘 揭露下進行許多變化與修改。因此，本發明之範蜂並非限 定於已揭露之實施例而係包含不悖離本發明之其他變化與 修改，其係如下列申請專利範圍所涵蓋之範疇。 【圖式簡單說明】 圖1係為一理想狀況下利用無線區域網路之定位方法的 示意圖。 圖2係為一非理想狀況下利用無線區域網路之定位方法 的示意圖。 圖3係為本發明幻影定位方法之一較佳實施例的示意圖。 圖4係為本發明決定一發射器之幻影位置之一較佳實施 例之示意圖。 【主要元件符號說明】 AP, ' AP2 ' AP3 發射器 AP!’、AP2,、AP3， 幻影位置 dl、d2、d3、dl，、d2,、d3. 距離 PP 備選幻影位置 PV 樞軸位置 X 已知位置 y 待測位置 116254.doc _ 10 -= At least three phantom positions of the transmitter must be found for positioning, but =: in the example only to find the phantom position of the transmitter Αρι, for example, for the other: 2 AP3 to find the phantom position method and transmitter Ap is the same, so it is not described. According to the present embodiment, the method of line phantom position includes the following steps for the feature area, for example: the range of a classroom 'determines the transmitter 用于 for positioning; 胄 the doorway or window of the classroom near the transmitter 或 or other The location for the radio signal to pass easily is selected as the location pv' and a known location is selected within the particular region; at the launch; J Α has = determined an alternate phantom location ΡΡ; the measured pivot positions PV and X... Line signal strength; according to the formula =&($)", the distance dx of the known position χ relative to the transmitter AP1 is derived, where sx, s~ are not already. The signal strength of the pivot position is set, dv is The distance between the x-axis position relative to the emitter AP, and 8^ are known parameters; the difference between the distance d X and the distance from the known position to each of the alternate phantom positions is derived by dividing the known position by the known position The actual distance of X to the emitter ΑΡι to obtain the distance error rate corresponding to each of the alternative phantom positions; finally, the alternative phantom position with the minimum distance error rate is selected as the phantom position AIV of the emitter 特定ι in a particular area. / Forbearance, the formula | = Ha is a way of using the ratio of the known signal strength to a known distance to obtain an unknown distance. The decision of the coefficients ^^ and 11 will change with the external environment, and there are many academic circles. The results of the analysis of the coefficients...therefore, the method of determining the coefficients 1^ and 11 is not the focus of the present invention, and the present invention can also use other well-known formulas to find the known position X relative to the emitter by the signal strength. The distance between ΑΡι is not limited to the above implementation of 116254.doc 1306952. In addition, the above embodiment uses only one known position to find the phantom position Ap of the emission II 在一 in a specific area, and then the same phantom can be utilized if any of the 4 points to be measured in the specific area are positioned. Position API, 〆, and 疋 position to reduce the complexity of the calculation. In other words, if it is necessary to find the corresponding phantom position for each point to be measured, it would be unrealistic to generate an excessive amount of work. In addition, if it is necessary to further improve the accuracy of the phantom position, according to another preferred embodiment of the present invention, a plurality of different known positions are shared in the specific area to share the same 柩 position, for each An alternate phantom position produces several distance error rates to average, and the alternate phantom position selected and having the smallest average distance error rate is the phantom position. Although the actual == method of finding the phantom position with several different known positions works slightly higher than the embodiment, but it is accompanied by the advantage of higher precision. Furthermore, in accordance with still another preferred embodiment of the present invention, the above domain may be further divided into a plurality of sub-specific regions, in which case each 疋 = = phantom region determined phantom location AP1, code t, AP3, It may not be AP', but the smaller the area of the specific area of the dice, the higher the reliability of the obtained phantom position 1 AI > 2, AP3' for positioning. The aforementioned phantom positioning method or the brain program instruction that determines the phantom position is completed. These computer programs refer to electrically programmable data processing devices to perform the method of phantoming his phantom position. These computer program instructions can also store == the recording medium (such as tape, diskette, CD-ROM, 'can be smashed, Ic memory, etc. 116254.doc 1306952 recorded media) for subsequent loading into the computer Used in. According to the embodiment provided in this table month, the actual emitter is replaced by the phantom emitter in the positioning calculation, so that the positioning accuracy can be improved without greatly increasing the workload and computational complexity. % to 2〇%. While the technical contents and features of the present invention are as described above, many variations and modifications can be made without departing from the teachings of the present invention. Therefore, the present invention is not limited to the disclosed embodiments but includes other variations and modifications of the present invention, which are within the scope of the following claims. [Simplified Schematic] FIG. 1 is a schematic diagram of a positioning method using a wireless local area network under ideal conditions. Figure 2 is a schematic diagram of a method of locating a wireless local area network in a non-ideal situation. 3 is a schematic diagram of a preferred embodiment of a phantom positioning method of the present invention. Figure 4 is a schematic illustration of one preferred embodiment of a phantom position for determining a transmitter of the present invention. [Key component symbol description] AP, ' AP2 ' AP3 transmitter AP!', AP2, AP3, phantom position dl, d2, d3, dl, d2, d3. Distance PP alternate phantom position PV pivot position X Known position y position to be tested 116254.doc _ 10 -