JP2006279201A - Radio tag reader - Google Patents
Radio tag reader Download PDFInfo
- Publication number
- JP2006279201A JP2006279201A JP2005091397A JP2005091397A JP2006279201A JP 2006279201 A JP2006279201 A JP 2006279201A JP 2005091397 A JP2005091397 A JP 2005091397A JP 2005091397 A JP2005091397 A JP 2005091397A JP 2006279201 A JP2006279201 A JP 2006279201A
- Authority
- JP
- Japan
- Prior art keywords
- output
- frequency channel
- tag reader
- correction value
- frequency
- 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
Links
- 230000003321 amplification Effects 0.000 claims abstract description 7
- 238000003199 nucleic acid amplification method Methods 0.000 claims abstract description 7
- 230000005540 biological transmission Effects 0.000 claims description 6
- 230000007613 environmental effect Effects 0.000 claims description 6
- 230000006870 function Effects 0.000 abstract description 4
- 238000000034 method Methods 0.000 description 4
- 238000010586 diagram Methods 0.000 description 1
- 230000005672 electromagnetic field Effects 0.000 description 1
- 238000009434 installation Methods 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
Images
Landscapes
- Near-Field Transmission Systems (AREA)
Abstract
Description
本発明は、無線タグのデータを無線で読み取る無線タグ読取装置に関する。 The present invention relates to a wireless tag reader that wirelessly reads data of a wireless tag.
近年、無線の固有タグ(RFID)を用いたシステムが注目されている。同一エリア内で複数の無線タグ読取装置を使用する場合、混信を防止するために別々の周波数を選択する必要がある。また無線タグの設置条件によっては、ちょうど電磁波の節(ヌルポイント)に位置したために読取性能が低下した場合など、ヌルポイントを移動させるために周波数を切り替える必要が生じる。このため無線タグ読取装置は使用周波数帯域内にて出力周波数を切り替えられる機能を持っている。 In recent years, a system using a wireless unique tag (RFID) has attracted attention. When using a plurality of RFID tag readers in the same area, it is necessary to select different frequencies in order to prevent interference. Also, depending on the installation conditions of the wireless tag, it may be necessary to switch the frequency in order to move the null point, for example, when the reading performance deteriorates because it is located at the node of the electromagnetic wave (null point). For this reason, the wireless tag reader has a function of switching the output frequency within the use frequency band.
しかし周波数を切り替えるとアンテナ回路を構成する電子部品、共振フィルタ、配線パターン長の電気的物理的要因によってその特性が変動してしまう。 However, when the frequency is switched, the characteristics fluctuate due to the electrical and physical factors such as the electronic components constituting the antenna circuit, the resonance filter, and the wiring pattern length.
増幅回路に起因する補正や環境変動に対する出力の安定化のため、通常は帰還式の出力制御回路が設けられている。しかしこの方法は、増幅回路全体の出力レベルを調整するといったもので各周波数チャネルの出力を一定にするという機能を有していない。 Usually, a feedback type output control circuit is provided for correction caused by the amplifier circuit and stabilization of output against environmental fluctuation. However, this method does not have a function of making the output of each frequency channel constant by adjusting the output level of the entire amplifier circuit.
電池を有しないパッシブ型の無線タグシステムにおいては、アンテナ出力変動が通信距離に影響を及ぼし、無線タグの認識率を低下させる原因となっていた。 In a passive wireless tag system that does not have a battery, antenna output fluctuations affect the communication distance, which causes a reduction in the wireless tag recognition rate.
電磁界強度が不足して無線タグを認識できないからといって単に出力を大きくすることは出来ず、各周波数チャンネルの出力は電波法で定められた値内で調整する必要がある。したがって環境変動に追従して従来のような増幅回路全体の出力安定化を行ったとしても各周波数チャンネル間に出力のバラツキが存在すると、ある周波数チャンネルで認識率が下がるということが生じる。 Just because the RFID tag cannot be recognized due to insufficient electromagnetic field strength, the output cannot simply be increased, and the output of each frequency channel needs to be adjusted within the value defined by the Radio Law. Therefore, even if the output of the entire amplifier circuit is stabilized following the environmental change, if the output varies between the frequency channels, the recognition rate may decrease in a certain frequency channel.
したがって本発明は上記に鑑みてなされたもので、その目的は、出力周波数チャンネル別の補正機能を設けることでアンテナの出力を一定にし、どの周波数においても安定な出力をRFIDタグに照射でき、安定した認識率を持つ無線タグ読み取り装置を提供することにある。 Therefore, the present invention has been made in view of the above, and its purpose is to provide a correction function for each output frequency channel so that the output of the antenna can be made constant, and the RFID tag can be irradiated with a stable output at any frequency. An object of the present invention is to provide a wireless tag reader having a recognized rate.
上記課題を解決するために、本発明の無線タグ読取装置は複数の無線タグの情報を電波により読み取る無線タグ読取装置において、
送信周波数および送信出力を制御するRF制御回路と、このRF制御回路の出力が供給される出力増幅回路と、この出力増幅回路の出力が供給されるアンテナ回路とを備え、
上記RF制御回路は周波数チャンネル別の出力補正値データを記録保持する手段と、周波数チャンネル切替時にこの出力補正値データを読み出す手段と、この出力補正値データに基づいて出力増幅回路の増幅率を制御する手段とを備えたことを特徴とするものである。
また、上記RF制御回路は、出力増幅回路の増幅率を制御して各周波数チャンネルの出力を一定にするように制御することを特徴とするものである。
In order to solve the above problems, a wireless tag reader of the present invention is a wireless tag reader that reads information of a plurality of wireless tags by radio waves.
An RF control circuit that controls the transmission frequency and transmission output, an output amplifier circuit that is supplied with the output of this RF control circuit, and an antenna circuit that is supplied with the output of this output amplifier circuit,
The RF control circuit records and holds the output correction value data for each frequency channel, reads the output correction value data when switching the frequency channel, and controls the amplification factor of the output amplifier circuit based on the output correction value data. And a means for performing.
Further, the RF control circuit is characterized in that the output of each frequency channel is controlled to be constant by controlling the amplification factor of the output amplifier circuit.
さらに、上記周波数チャンネル別の出力補正値データを記録保持する手段は、あらかじめ周波数チャンネル毎の補正値をメモリ上のテーブルにプリセットしておくことを特徴とするものである。 Further, the means for recording and holding the output correction value data for each frequency channel presets the correction value for each frequency channel in a table on the memory in advance.
また、上記周波数チャンネル別の出力補正値データは、各周波数チャンネルに対し環境条件を変化させた時のアンテナ出力特性の変動に基づくデータであることを特徴とするものである。 The output correction value data for each frequency channel is data based on fluctuations in antenna output characteristics when environmental conditions are changed for each frequency channel.
以上説明したように本発明によれば、プリセットされた出力補正値から各周波数チャンネルの出力を一定にできるので周波数を変えても読み取れるエリアは同じとなり、安定した認識率を得ることができる。 As described above, according to the present invention, since the output of each frequency channel can be made constant from the preset output correction value, the read area is the same even if the frequency is changed, and a stable recognition rate can be obtained.
以下本発明の実施形態につき詳細に説明する。図１は本発明の一実施例を示す。本実施例はCH1からCH４の四つの周波数チャンネルを切り替えて使用することを前提としている。 Hereinafter, embodiments of the present invention will be described in detail. FIG. 1 shows an embodiment of the present invention. This embodiment is premised on switching and using four frequency channels from CH1 to CH4.
無線タグ読取装置は送信周波数と送信出力を制御するRF制御部１２、出力レベルをある規定値に増幅する出力増幅回路１３とアンテナ回路１４から構成される。本発明ではRF制御部１２にメモリ１１が接続され、メモリ１１の構成例として、図２に示すような周波数チャンネル間の出力差を補正値とする周波数チャンネル出力補正テーブル２１が設けられている。 The wireless tag reader includes an RF control unit 12 that controls the transmission frequency and transmission output, an output amplifier circuit 13 that amplifies the output level to a specified value, and an antenna circuit 14. In the present invention, a memory 11 is connected to the RF control unit 12, and as a configuration example of the memory 11, a frequency channel output correction table 21 having an output difference between frequency channels as a correction value as shown in FIG. 2 is provided.
環境変化に起因する増幅器の特性変動を補正し、出力を一定にするために次のような方法がとられる。出力増幅回路１３の出力を分岐してRF制御部１２にフィードバックし、出力振幅あるいは電力を検出することにより出力を一定に保つことができる。しかしながら、この補正方法では全体的なレベル補正を目的としているので出力増幅回路１３の後段に配置されたアンテナ回路１４の出力特性が周波数によって違う場合にはアンテナ出力レベルは図４のようにバラバラとなり、無線タグ認識率を低下させる原因となる。上述した出力の補正方法を基本調整とし、更にアンテナ回路１４の周波数チャンネル別の出力を微調整する。 The following method is used to correct the characteristic variation of the amplifier due to the environmental change and make the output constant. The output can be kept constant by branching the output of the output amplifier circuit 13 and feeding it back to the RF controller 12 and detecting the output amplitude or power. However, since this correction method aims at overall level correction, when the output characteristics of the antenna circuit 14 arranged at the subsequent stage of the output amplifier circuit 13 differ depending on the frequency, the antenna output level varies as shown in FIG. This causes a reduction in the wireless tag recognition rate. The output correction method described above is used as a basic adjustment, and the output of the antenna circuit 14 for each frequency channel is finely adjusted.
まずメモリ１１内に周波数チャンネル出力補正テーブル２１を設けて、あらかじめアンテナ回路の周波数チャンネル出力が一定になるような補正値を記録しておく。次に、周波数チャンネル切替回路１４を切り替える際に上記メモリ１１内に設けられた周波数チャンネル出力補正テーブル２１を参照する。 First, a frequency channel output correction table 21 is provided in the memory 11 and a correction value is recorded in advance so that the frequency channel output of the antenna circuit becomes constant. Next, the frequency channel output correction table 21 provided in the memory 11 is referred to when switching the frequency channel switching circuit 14.
図２の周波数チャンネル出力補正テーブル２１において周波数チャンネルCH1からCH４の補正すべき値は、例えば温度２０℃で、それぞれD1,D2,D3,D4となる。この補正値はある設定したい出力電力と各周波数チャンネルの補正前の出力との電力比を表したもので構わない。周波数チャンネルを切り替える命令を上位装置（例えば無線タグ読取装置に接続された外部コンピュータ）から受けた場合、対応する周波数チャンネルの補正値を周波数チャンネル出力補正テーブル２１から読み出し、その補正値分に対応する制御値を求めて出力増幅回路１３の増幅率を変化させ、各周波数チャンネル出力が一定になるように制御する。これにより図３に示すように各周波数チャンネル出力は等しくなる。 In the frequency channel output correction table 21 of FIG. 2, the values to be corrected for the frequency channels CH1 to CH4 are D1, D2, D3, and D4, respectively, at a temperature of 20 ° C., for example. This correction value may represent a power ratio between an output power desired to be set and an output before correction of each frequency channel. When a command for switching the frequency channel is received from a higher-level device (for example, an external computer connected to the wireless tag reader), the corresponding frequency channel correction value is read from the frequency channel output correction table 21 and corresponds to the correction value. A control value is obtained and the amplification factor of the output amplifier circuit 13 is changed to control each frequency channel output to be constant. As a result, the output of each frequency channel becomes equal as shown in FIG.
上述の説明では、単純化してある温度のときの各周波数チャンネルの出力特性の差異を補正する説明をしたが、周波数チャンネル出力補正テーブル２１は温度に加え湿度など環境条件を変数にして補正をすることもできる。この場合、無線タグ読取装置内に温度または湿度センサーを設けるなどして、その情報をもとに周波数チャンネル出力補正テーブル２１の補正値を読み出し補正を行う。 In the above description, a description has been given of correcting the difference in output characteristics of each frequency channel at a simplified temperature. However, the frequency channel output correction table 21 performs correction using environmental conditions such as humidity in addition to temperature as variables. You can also In this case, a temperature or humidity sensor is provided in the RFID tag reader, and the correction value of the frequency channel output correction table 21 is read and corrected based on the information.
このように構成された本発明の実施形態に係る無線タグ読取装置によれば、プリセットされた出力補正値から各周波数チャンネルの出力を一定にできるので周波数を変えても読み取れるエリアは同じとなり、安定した認識率を得ることができる。 According to the wireless tag reader according to the embodiment of the present invention configured as described above, since the output of each frequency channel can be made constant from the preset output correction value, the area that can be read even if the frequency is changed is the same, and stable. Recognition rate can be obtained.
なお、本発明は上記実施形態をそのままに限定されるものではなく、実施段階でその要旨を逸脱しない範囲で具体化できる。 Note that the present invention is not limited to the above-described embodiment as it is, and can be embodied without departing from the spirit of the invention at the stage of implementation.
１１…メモリ
１２…RF制御部
１３…出力増幅回路
１４…アンテナ回路
２１…周波数チャンネル出力補正テーブル
DESCRIPTION OF SYMBOLS 11 ... Memory 12 ... RF control part 13 ... Output amplifier circuit 14 ... Antenna circuit 21 ... Frequency channel output correction table
Claims (4)
送信周波数および送信出力を制御するRF制御回路と、このRF制御回路の出力が供給される出力増幅回路と、この出力増幅回路の出力が供給されるアンテナ回路とを備え、
上記RF制御回路は周波数チャンネル別の出力補正値データを記録保持する手段と、周波数チャンネル切替時にこの出力補正値データを読み出す手段と、この出力補正値データに基づいて出力増幅回路の増幅率を制御する手段とを備えたことを特徴とする無線タグ読取装置。 In a wireless tag reader that reads information of a plurality of wireless tags by radio waves,
An RF control circuit that controls the transmission frequency and transmission output, an output amplifier circuit that is supplied with the output of this RF control circuit, and an antenna circuit that is supplied with the output of this output amplifier circuit,
The RF control circuit records and holds the output correction value data for each frequency channel, reads the output correction value data when switching the frequency channel, and controls the amplification factor of the output amplifier circuit based on the output correction value data. And a wireless tag reader.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2005091397A JP2006279201A (en) | 2005-03-28 | 2005-03-28 | Radio tag reader |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2005091397A JP2006279201A (en) | 2005-03-28 | 2005-03-28 | Radio tag reader |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2006279201A true JP2006279201A (en) | 2006-10-12 |
Family
ID=37213534
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2005091397A Pending JP2006279201A (en) | 2005-03-28 | 2005-03-28 | Radio tag reader |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2006279201A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100811118B1 (en) | 2005-06-10 | 2008-03-06 | 세이코 엡슨 가부시키가이샤 | Droplet discharge method |
| JP2011101086A (en) * | 2009-11-04 | 2011-05-19 | Denso Wave Inc | Portable terminal |
| KR101258296B1 (en) * | 2006-11-27 | 2013-04-25 | 주식회사 엘지씨엔에스 | Radio Frequency sensitiveity revision method and the device of Radio Frequency card terminal |
| KR101271578B1 (en) | 2008-01-31 | 2013-06-05 | 인텔렉추얼디스커버리 주식회사 | RFID system and communication method thereof |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH10198771A (en) * | 1997-01-08 | 1998-07-31 | Shinko Electric Co Ltd | Non-contact ic card, reader/writer, and communication equipment for non-contact ic card |
| JP2001358608A (en) * | 2000-06-09 | 2001-12-26 | Seiko Precision Inc | Transmitter-receiver and data carrier system using the same |
| JP2003318748A (en) * | 2002-04-24 | 2003-11-07 | Nec Corp | Portable terminal and its frequency characteristics adjusting method |
| JP2004221663A (en) * | 2003-01-09 | 2004-08-05 | Matsushita Electric Ind Co Ltd | Radio communication equipment |
-
2005
- 2005-03-28 JP JP2005091397A patent/JP2006279201A/en active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH10198771A (en) * | 1997-01-08 | 1998-07-31 | Shinko Electric Co Ltd | Non-contact ic card, reader/writer, and communication equipment for non-contact ic card |
| JP2001358608A (en) * | 2000-06-09 | 2001-12-26 | Seiko Precision Inc | Transmitter-receiver and data carrier system using the same |
| JP2003318748A (en) * | 2002-04-24 | 2003-11-07 | Nec Corp | Portable terminal and its frequency characteristics adjusting method |
| JP2004221663A (en) * | 2003-01-09 | 2004-08-05 | Matsushita Electric Ind Co Ltd | Radio communication equipment |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100811118B1 (en) | 2005-06-10 | 2008-03-06 | 세이코 엡슨 가부시키가이샤 | Droplet discharge method |
| KR101258296B1 (en) * | 2006-11-27 | 2013-04-25 | 주식회사 엘지씨엔에스 | Radio Frequency sensitiveity revision method and the device of Radio Frequency card terminal |
| KR101271578B1 (en) | 2008-01-31 | 2013-06-05 | 인텔렉추얼디스커버리 주식회사 | RFID system and communication method thereof |
| JP2011101086A (en) * | 2009-11-04 | 2011-05-19 | Denso Wave Inc | Portable terminal |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| EP1986331B1 (en) | A method for making a power amplifier support multi-power, a radio frequency module and a testing method | |
| JP4977438B2 (en) | Communication device and portable communication terminal using the same | |
| JP4049112B2 (en) | Electronic equipment | |
| US20060139099A1 (en) | Intelligent rf power control for wireless modem devices | |
| JP5332468B2 (en) | Receiver circuit | |
| JP2009512054A (en) | Electrical circuit for contactless reader device | |
| JP2010504683A (en) | m RFID reader machine | |
| JP2006279201A (en) | Radio tag reader | |
| CN110728338B (en) | RFID reader-writer system and power calibration method | |
| JP2006279200A (en) | Radio tag reader | |
| US6559755B1 (en) | Storage device and method, information processing apparatus and method, and provision medium therefor | |
| JP2005073113A (en) | Non-contact ic card | |
| JP6529919B2 (en) | Wireless transmission apparatus and method | |
| KR20080019096A (en) | Low power rfid system and method, reader applied to the same | |
| KR20210033749A (en) | Appliance, appliance network system and connection method thereof | |
| US20080136548A1 (en) | Impedance matching device of sensor node and impedance matching method of sensor node | |
| KR20160030673A (en) | Method for minimizing a consuming electric power and an electronic device implementing the same | |
| JP4304296B2 (en) | Transmission power control circuit and wireless communication apparatus provided with transmission power control circuit | |
| JPH11234050A (en) | Power amplifier | |
| JP2004220492A (en) | Non-contact ic card reader/writer | |
| JP2006309425A (en) | Rfid reader/writer device | |
| JP4985732B2 (en) | IC tag reading / writing device, electronic device, and IC tag reading / writing method | |
| JP2010041100A (en) | Distortion compensation device, radio communication device, distortion compensation method, and radio communication method | |
| KR20040043199A (en) | Transponder with a changeable circuit configuration | |
| JP3933165B2 (en) | Transmission power control apparatus and method, computer program for transmission power control apparatus, and radio transmitter |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| A621 | Written request for application examination |
Free format text: JAPANESE INTERMEDIATE CODE: A621 Effective date: 20080222 |
|
| A131 | Notification of reasons for refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A131 Effective date: 20100713 |
|
| A02 | Decision of refusal |
Free format text: JAPANESE INTERMEDIATE CODE: A02 Effective date: 20101221 |