JP3389178B2 - OFDM diversity receiver - Google Patents
OFDM diversity receiverInfo
- Publication number
- JP3389178B2 JP3389178B2 JP34048899A JP34048899A JP3389178B2 JP 3389178 B2 JP3389178 B2 JP 3389178B2 JP 34048899 A JP34048899 A JP 34048899A JP 34048899 A JP34048899 A JP 34048899A JP 3389178 B2 JP3389178 B2 JP 3389178B2
- Authority
- JP
- Japan
- Prior art keywords
- carrier
- ofdm
- receiving
- diversity
- reliability information
- 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.)
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Description
【０００１】[0001]
【発明の属する技術分野】本発明は、複数のＯＦＤＭ
（直交周波数分割多重）復調回路を用いてＯＦＤＭのキ
ャリア単位でダイバーシチ受信を行うＯＦＤＭダイバー
シチ受信装置に関する。TECHNICAL FIELD The present invention relates to a plurality of OFDMs.
The present invention relates to an OFDM diversity receiving apparatus that performs diversity reception on an OFDM carrier basis using a (orthogonal frequency division multiplexing) demodulation circuit.
【０００２】[0002]
【従来の技術】近年、地上テレビジョン放送システムの
デジタル化の研究が盛んであるが、欧州と日本において
は直交周波数分割多重（以下、ＯＦＤＭという）方式が
伝送方式として採用されることが決定され、特に欧州に
おいては規格化が完了し実用レベルに達している。この
ＯＦＤＭ方式は、広帯域信号を互いに直交する多数の搬
送波（以下、サブキャリアという）で伝送することによ
り、地上テレビジョン放送において必須の伝送条件であ
るマルチパス伝搬路における耐遅延干渉特性を改善でき
る等の特徴がある。また、このＯＦＤＭ方式は、伝送デ
ータを複数のキャリアに分散して伝送しているため、誤
り訂正を組み合わせることにより、マルチパス歪などの
周波数選択性の伝送路歪に対して優れた伝送特性を示す
ことが知られている。2. Description of the Related Art In recent years, much research has been conducted on the digitization of terrestrial television broadcasting systems. In Europe and Japan, it has been decided to adopt an orthogonal frequency division multiplexing (hereinafter referred to as OFDM) system as a transmission system. , Especially in Europe, the standardization has been completed and it has reached a practical level. In this OFDM system, by transmitting a wideband signal by a large number of carriers (hereinafter referred to as subcarriers) that are orthogonal to each other, it is possible to improve delay interference resistance characteristics in a multipath propagation path which is an essential transmission condition in terrestrial television broadcasting. There are features such as. Further, in this OFDM method, since transmission data is distributed and transmitted to a plurality of carriers, by combining error correction, it is possible to obtain excellent transmission characteristics against frequency-selective transmission path distortion such as multipath distortion. It is known to show.
【０００３】ところで、地上デジタル放送にあっては、
移動受信などの厳しい受信条件下において、さらに伝送
特性を向上させる方法として、ＯＦＤＭのキャリア単位
でダイバーシチ受信を行うことが提案されている。ダイ
バーシチ受信方式として代表的な合成ダイバーシチで
は、一般に２系統のＯＦＤＭ復調装置で得られる復調デ
ータをＯＦＤＭのキャリア単位で受信電力に応じて合成
する。この場合、２系統の伝送路応答は異なるため、周
波数選択性の伝送路歪を大幅に改善することができる。
また、移動受信時に生じる時間方向の変動も同様に改善
される。このことは、受信電力の大きい系統を選択する
選択ダイバーシチによっても、合成ダイバーシチより特
性は劣るものの、同様の効果が得られる。By the way, in terrestrial digital broadcasting,
It has been proposed to perform diversity reception on a carrier-by-OFDM basis as a method for further improving transmission characteristics under severe reception conditions such as mobile reception. In typical diversity diversity as a diversity reception system, demodulated data generally obtained by two systems of OFDM demodulators are combined in OFDM carrier units according to received power. In this case, since the two systems have different transmission line responses, frequency selective transmission line distortion can be greatly improved.
Further, the fluctuation in the time direction that occurs during mobile reception is similarly improved. This means that even if the selection diversity for selecting a system with a large received power is inferior to the combined diversity, the same effect can be obtained.
【０００４】[0004]
【発明が解決しようとする課題】しかしながら、従来の
一般的な手法によるＯＦＤＭダイバーシチ受信装置で
は、複数系統の復調データを合成または選択する際の評
価指標として、受信電力の大きさを用いている。しか
し、特定の周波数が妨害を受けている場合などでは、受
信電力の大きい系統が受信品質が良いとは限らない。However, in the OFDM diversity receiver according to the conventional general method, the magnitude of the received power is used as an evaluation index when synthesizing or selecting demodulated data of a plurality of systems. However, when a specific frequency is disturbed, a system with a large received power does not always have a good reception quality.
【０００５】例えば、ＯＦＤＭによるデジタルＴＶ放送
帯域にアナログＴＶ放送波が入ると、その映像搬送波や
音声搬送波が妨害波となってＯＦＤＭの特定のキャリア
が歪んでしまうが、そのキャリアの受信電力は増大して
いる。このようなＯＦＤＭ信号を従来の方式でダイバー
シチ受信した場合、損傷を受けたキャリアのデータを用
いて全体の誤り訂正を行うことになり、誤り訂正の特性
が劣化してしまうことになる。For example, when an analog TV broadcast wave enters the digital TV broadcast band by OFDM, the video carrier and audio carrier become an interfering wave and the specific carrier of OFDM is distorted, but the received power of the carrier increases. is doing. If you diversity receiving such OFDM signals in a conventional manner, it will be performing overall error correction using the data of the carrier damaged, so that the characteristics of error correction is degraded.
【０００６】そこで本発明では、特定のキャリアが妨害
を受けた場合でも、誤り訂正の特性が向上するように効
果的にダイバーシチを行うことのできるＯＦＤＭダイバ
ーシチ受信装置を提供することを目的とする。Therefore, an object of the present invention is to provide an OFDM diversity receiver capable of effectively performing diversity so that the error correction characteristic is improved even when a specific carrier is disturbed.
【０００７】[0007]
【課題を解決するための手段】上記の目的を達成するた
めに本発明は、複数の受信系それぞれに設けられ、互い
に独立してＯＦＤＭ（直交周波数分割多重）信号を受信
し、この受信信号を時間領域から周波数領域に変換して
キャリア毎の信号を取り出し、各キャリアに割り当てら
れている信号データを復調する複数のＯＦＤＭ受信・復
調手段と、前記複数の受信系それぞれのＯＦＤＭ受信・
復調手段で得られる各キャリアの復調データを入力して
キャリア単位でダイバーシチ処理を行うダイバーシチ処
理手段とを備えるＯＦＤＭダイバーシチ受信装置におい
て、前記複数の受信系それぞれのＯＦＤＭ受信・復調手
段で得られる前記キャリア毎の復調データに及ぼされて
いる妨害の強度を判定し、この判定結果に基づいて前記
復調データの信頼性の度合を示す信頼性情報を前記キャ
リア毎に求める信頼性情報取得手段と、前記信頼性情報
取得手段で得られる前記複数の受信系のキャリア毎の信
頼性情報に基づいて前記ダイバーシチ処理手段でダイバ
ーシチ処理するキャリアを制限するダイバーシチ処理制
御手段とを具備する構成としている。In order to achieve the above object, the present invention is provided in each of a plurality of receiving systems, receives OFDM (orthogonal frequency division multiplexing) signals independently of each other, and receives the received signals. A plurality of OFDM receiving / demodulating means for converting the time domain to the frequency domain to extract a signal for each carrier and demodulating signal data assigned to each carrier, and OFDM receiving / demodulating means for each of the plurality of receiving systems.
In an OFDM diversity receiver including a diversity processing means for inputting demodulation data of each carrier obtained by the demodulation means and performing diversity processing in carrier units, the carrier obtained by the OFDM reception / demodulation means of each of the plurality of reception systems Reliability information acquiring means for determining the strength of the interference exerted on the demodulated data for each carrier, and for obtaining reliability information indicating the degree of reliability of the demodulated data for each carrier based on the determination result; And diversity processing control means for limiting the carriers to be diversity-processed by the diversity processing means based on the reliability information for each carrier of the plurality of reception systems obtained by the property information acquisition means.
【０００８】すなわち、上記の構成では、各受信系でキ
ャリア毎の復調データが受けている妨害の強度を判定
し、その判定結果から各復調データの信頼性を求め、そ
の信頼性に基づいてダイバーシチ処理時のキャリアを制
限するようにしているので、周波数選択性の妨害により
阻害されたキャリアの復調データを除いてダイバーシチ
受信することが可能となり、誤り訂正の特性が向上する
ようになる。That is, in the above configuration, the strength of the interference received by the demodulated data for each carrier in each receiving system is determined, the reliability of each demodulated data is obtained from the result of the determination, and the diversity is calculated based on the reliability. Since the carrier at the time of processing is limited, diversity reception can be performed except for demodulated data of the carrier which is disturbed by the interference of frequency selectivity, and the error correction characteristic is improved.
【０００９】[0009]
【発明の実施の形態】以下、図面を参照して本発明の実
施の形態を詳細に説明する。BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
【００１０】（第１の実施形態）図１は、本発明の第１
の実施形態として、第１及び第２の受信系の各復調出力
を用いて、キャリア単位で合成ダイバーシチを行う場合
のＯＦＤＭダイバーシチ受信装置の構成を示すブロック
図である。(First Embodiment) FIG. 1 shows a first embodiment of the present invention.
FIG. 3 is a block diagram showing a configuration of an OFDM diversity receiving apparatus in the case of performing combined diversity on a carrier-by-carrier basis using demodulated outputs of the first and second reception systems as an embodiment of FIG.
【００１１】図１に示す第１の受信系において、アンテ
ナ１１で受信されたＯＦＤＭ変調波は、チューナ１２で
所定チャンネルが選択された後、Ａ／Ｄ（アナログ／デ
ジタル）変換器１３によってデジタル信号に変換され
る。Ａ／Ｄ変換器１３の出力はＡＧＣ（自動利得制御）
回路１４に供給される。このＡＧＣ回路１４は、Ａ／Ｄ
変換器１３の出力からチューナ１２の出力レベルを検出
し、そのレベルが所定レベルとなるようにチューナ１２
にゲイン制御電圧を供給するものである。In the first receiving system shown in FIG. 1, an OFDM modulated wave received by an antenna 11 is converted into a digital signal by an A / D (analog / digital) converter 13 after a predetermined channel is selected by a tuner 12. Is converted to. The output of the A / D converter 13 is AGC (automatic gain control)
It is supplied to the circuit 14. This AGC circuit 14 is an A / D
The output level of the tuner 12 is detected from the output of the converter 13, and the tuner 12 is adjusted so that the level becomes a predetermined level.
The gain control voltage is supplied to.
【００１２】一方、Ａ／Ｄ変換器１３の出力は、ＩＱ復
調回路１５により複素ベースバンド信号に変換された
後、ＦＦＴ（高速フーリエ変換）回路１６に供給され
る。このＦＦＴ回路１６は、ＦＦＴ演算により時間軸上
のＯＦＤＭ変調波を周波数軸上のデータに変換する。す
なわち、ＦＦＴ回路１６の出力は、各キャリアの振幅及
び位相を示す。On the other hand, the output of the A / D converter 13 is converted into a complex baseband signal by the IQ demodulation circuit 15 and then supplied to an FFT (Fast Fourier Transform) circuit 16. The FFT circuit 16 converts the OFDM modulated wave on the time axis into data on the frequency axis by FFT calculation. That is, the output of the FFT circuit 16 indicates the amplitude and phase of each carrier.
【００１３】ＦＦＴ回路１６の出力は復調回路１７に供
給される。この復調回路１７は各キャリアの伝送路応答
を推定して復調処理を行う。この伝送路応答の推定は、
キャリアの変調方式が差動変調の場合は各キャリアの１
シンボル前のデータを用いて行われ、変調方式がＱＡＭ
などの場合は伝送信号に多重されたパイロット信号など
を用いて行われる。以上により、ＯＦＤＭの各キャリア
のデータが復調される。The output of the FFT circuit 16 is supplied to the demodulation circuit 17. The demodulation circuit 17 estimates the transmission line response of each carrier and performs demodulation processing. This transmission line response estimation is
1 for each carrier when the carrier modulation method is differential modulation
The modulation method is QAM, which is performed using the data before the symbol.
In such cases, the pilot signal or the like multiplexed with the transmission signal is used. By the above, the data of each carrier of OFDM is demodulated.
【００１４】また、ＦＦＴ回路１６及び復調回路１７の
出力は、信頼性情報算出回路１８に供給される。この信
頼性情報算出回路１８において、電力検出回路１８１は
ＦＦＴ回路１６の出力を用いて各キャリアの受信電力を
検出する。一方、分散検出回路１８２は、復調回路１７
から供給される各キャリアのＩデータ、Ｑデータの判定
を行い、本来の送信点からの分散の度合をキャリア毎に
求める。The outputs of the FFT circuit 16 and the demodulation circuit 17 are supplied to the reliability information calculation circuit 18. In the reliability information calculation circuit 18, the power detection circuit 181 detects the reception power of each carrier using the output of the FFT circuit 16. On the other hand, the dispersion detection circuit 182 is connected to the demodulation circuit 17
The I data and Q data of each carrier supplied from the above are determined, and the degree of dispersion from the original transmission point is obtained for each carrier.
【００１５】ここで、図２に分散検出回路１８２の具体
的な構成を例示する。図２において、入力された各キャ
リアのＩデータ、Ｑデータは、硬判定回路Ａ１、Ａ３で
それぞれ受信点に最も近い基準点が判定される。硬判定
回路Ａ１、Ａ３の入力及び出力は、それぞれ差分回路Ａ
２、Ａ４に供給されて、ＩＱデータそれぞれについて基
準点からの差分が検出される。差分回路Ａ２、Ａ４の出
力は共に自乗和検出回路Ａ５に供給されて両信号の自乗
和が求められ、積分回路Ａ６でキャリア毎に積分される
ことで平均化され、これによってキャリア毎の分散値が
求められる。Here, FIG. 2 illustrates a specific configuration of the dispersion detection circuit 182. In FIG. 2, with respect to the input I data and Q data of each carrier, the hard decision circuits A1 and A3 determine the reference point that is the closest to the reception point. The inputs and outputs of the hard decision circuits A1 and A3 are the difference circuit A, respectively.
2 and A4, the difference from the reference point is detected for each IQ data. The outputs of the difference circuits A2 and A4 are both supplied to the sum of squares detection circuit A5, the sum of squares of both signals is obtained, and integrated by each carrier in the integrator circuit A6 to be averaged. Is required.
【００１６】分散検出回路１８２の出力は、２系統に分
岐されてしきい値算出回路１８３としきい値判定回路１
８４に供給される。しきい値算出回路１８３は、全キャ
リアの分散の平均値をもとに各キャリアの分散を判定す
るためのしきい値を算出する。しきい値算出回路１８３
の出力はしきい値判定回路１８４に供給される。このし
きい値判定回路１８４は、各キャリアの分散値がしきい
値より大きい場合は、そのキャリアは妨害を受けている
と判定する。The output of the dispersion detection circuit 182 is branched into two systems, which are the threshold value calculation circuit 183 and the threshold value judgment circuit 1.
84. The threshold calculation circuit 183 calculates a threshold for determining the dispersion of each carrier based on the average value of the dispersion of all carriers. Threshold calculation circuit 183
Is output to the threshold value determination circuit 184. The threshold value determination circuit 184 determines that the carrier is disturbed when the dispersion value of each carrier is larger than the threshold value.
【００１７】図３（ａ）、（ｂ）に一例を示す。図３
（ａ）はＯＦＤＭ波の帯域内に周波数選択性の妨害波が
混入している様子を示し、図３（ｂ）は各キャリアの分
散の平均値から求められた判定しきい値を示すものであ
る。図３（ａ）に示すように、雑音はＯＦＤＭ波に対し
て一様に分布しているが、ＯＦＤＭ波の受信レベルが十
分高い場合には、図３（ｂ）に示すように分散値が判定
しきい値を越えることはない。図３（ａ）に示すよう
に、ＯＦＤＭ波の帯域内に周波数選択性の妨害波が混入
すると、その妨害波の影響により、図３（ｂ）に示すよ
うにある特定の周波数で分散値が大きくなり、判定しき
い値を越えるようになる。しきい値判定回路１８４は、
しきい値を越える周波数を求め、その周波数に対応する
キャリアは妨害を受けていると判定する。An example is shown in FIGS. 3 (a) and 3 (b). Figure 3
FIG. 3A shows that a frequency-selective interfering wave is mixed in the band of the OFDM wave, and FIG. 3B shows the judgment threshold value obtained from the average value of the dispersion of each carrier. is there. As shown in FIG. 3A, noise is uniformly distributed with respect to the OFDM wave, but when the reception level of the OFDM wave is sufficiently high, the variance value is as shown in FIG. 3B. The judgment threshold is never exceeded. As shown in FIG. 3A, when a frequency-selective interfering wave is mixed in the OFDM wave band, the influence of the interfering wave causes a dispersion value at a specific frequency as shown in FIG. 3B. It becomes larger and exceeds the judgment threshold. The threshold determination circuit 184 is
The frequency exceeding the threshold value is obtained, and it is determined that the carrier corresponding to the frequency is disturbed.
【００１８】上記しきい値判定回路１８４の判定結果は
補正回路１８５に供給される。この補正回路１８５は、
妨害を受けていると判定されたキャリアの受信電力を０
に補正する。この結果、補正回路１８５の出力は、妨害
判定の結果を含む各キャリアの信頼性情報を示すことに
なる。The judgment result of the threshold judgment circuit 184 is supplied to the correction circuit 185. This correction circuit 185 is
Set the received power of the carrier determined to be disturbed to 0
Correct to. As a result, the output of the correction circuit 185 indicates the reliability information of each carrier including the result of the interference determination.
【００１９】一方、図１に示す第２の受信系において、
アンテナ１９で受信されたＯＦＤＭ信号は、チューナ２
０で第１の受信系のチューナ１２と同じチャンネルが選
択された後、Ａ／Ｄ変換器２１、ＡＧＣ回路２２、ＩＱ
復調回路２３、ＦＦＴ回路２４及び復調回路２５によ
り、第１の受信系と同様にして各キャリアのデータが復
調されて信頼性情報算出回路２６に供給される。この信
頼性情報算出回路２６は、第１の受信系における信頼性
情報算出回路１８と同様に、電力検出回路２６１、分散
検出回路２６２、しきい値算出回路２６３、しきい値判
定回路２６４及び補正回路２６５で構成され、各キャリ
アの復調データから各キャリアの信頼性情報が検出され
る。On the other hand, in the second receiving system shown in FIG.
The OFDM signal received by the antenna 19 is transmitted to the tuner 2
After selecting the same channel as the tuner 12 of the first receiving system at 0, the A / D converter 21, AGC circuit 22, IQ
Data of each carrier is demodulated by the demodulation circuit 23, the FFT circuit 24, and the demodulation circuit 25, and is supplied to the reliability information calculation circuit 26. This reliability information calculation circuit 26 is similar to the reliability information calculation circuit 18 in the first reception system, and includes a power detection circuit 261, a dispersion detection circuit 262, a threshold value calculation circuit 263, a threshold value determination circuit 264, and a correction. The circuit 265 is configured to detect the reliability information of each carrier from the demodulated data of each carrier.
【００２０】信頼性情報検出回路１８、２６の出力は重
み付け係数算出回路２７に供給される。この重み付け係
数算出回路２７は、キャリア毎に第１の受信系と第２の
受信系それぞれの信頼性情報を比較し、両者の比を求め
て各受信系の重み付け係数を算出するものである。一方
の受信系のキャリアが妨害を受けている場合、その信頼
性情報は０になっているので、結果として妨害を受けて
いる受信系の重み付け係数は０になる。第１、第２の受
信系それぞれの信頼性情報がともに０の場合は、重み付
け係数に意味はなくなるが、例えば２系統ともに０を出
力するものとする。The outputs of the reliability information detection circuits 18 and 26 are supplied to the weighting coefficient calculation circuit 27. The weighting coefficient calculation circuit 27 compares the reliability information of the first receiving system and the reliability information of the second receiving system for each carrier and obtains the ratio between them to calculate the weighting coefficient of each receiving system. When the carrier of one receiving system is disturbed, the reliability information is 0, and as a result, the weighting coefficient of the receiving system being disturbed is 0. When the reliability information of both the first and second receiving systems is 0, the weighting coefficient has no meaning, but for example, both systems output 0.
【００２１】重み付け係数算出回路２７によって求めら
れた各受信系の重み付け係数は、合成ダイバーシチ回路
２８に供給される。この合成ダイバーシチ回路２８にお
いて、各キャリアの復調データの合成は、第１及び第２
の受信系の復調データをそれぞれ乗算器２８１、２８２
を用いて対応する重み付け係数で重み付けし、加算器２
８３で合成することにより達成される。このとき、一方
が妨害を受けている場合、その重み付け係数は０になっ
ているので、妨害の影響を除去した合成ダイバーシチが
可能である。また、各キャリアの信頼性情報も、乗算器
２８４、２８５、加算器２８６を用いて同様に合成さ
れ、復調データの合成と同様に、一方が妨害を受けてい
る場合の影響を除去した合成が可能である。また、両方
ともに妨害を受けている場合は、合成後の信頼性情報も
０になり、後段の誤り訂正回路２９で消失訂正を行うこ
とが可能となる。The weighting coefficient of each receiving system obtained by the weighting coefficient calculating circuit 27 is supplied to the combining diversity circuit 28. In the combining diversity circuit 28, the demodulated data of each carrier are combined in the first and second
Demodulation data of the reception system of the multipliers 281 and 282, respectively.
Are weighted with the corresponding weighting factors using
This is achieved by synthesizing at 83. At this time, when one of them is disturbed, the weighting coefficient is 0, so that it is possible to perform the combining diversity in which the influence of the disturbance is removed. Further, the reliability information of each carrier is similarly combined by using the multipliers 284, 285 and the adder 286, and like the combination of demodulated data, the combination in which the influence when one is disturbed is removed is obtained. It is possible. Further, when both are disturbed, the reliability information after combining is also 0, and the erasure correction can be performed by the error correction circuit 29 in the subsequent stage.
【００２２】合成ダイバーシチ回路２８によって得られ
た各キャリアの復調データ及び信頼性情報は誤り訂正回
路２９に供給され、誤り訂正が施されて受信データが復
号される。The demodulation data and reliability information of each carrier obtained by the combining diversity circuit 28 are supplied to the error correction circuit 29, where error correction is performed and the received data is decoded.
【００２３】以上により、本実施形態の構成によれば、
キャリア妨害の悪影響を受けることなくキャリア単位の
合成ダイバーシチを行うことができると共に、各キャリ
アの信頼性情報も合成して誤り訂正回路２９に供給する
ようにしているので、ダイバーシチ受信においても信頼
性情報を用いて誤り訂正の特性を向上させることができ
る。As described above, according to the configuration of this embodiment,
Since the combining diversity can be performed on a carrier-by-carrier basis without being adversely affected by the carrier interference, and the reliability information of each carrier is also combined and supplied to the error correction circuit 29, the reliability information is also received in the diversity reception. Can be used to improve the error correction characteristics.
【００２４】尚、図１に示す実施形態では、復調データ
だけでなく信頼性情報も重み付け係数により重み付けし
て合成しているが、信頼性情報に関しては、値の大きい
方を選択して出力するようにしても同様の効果が得られ
る。In the embodiment shown in FIG. 1, not only the demodulated data but also the reliability information is weighted and combined by the weighting coefficient. However, for the reliability information, the one with the larger value is selected and output. Even if it does so, the same effect can be obtained.
【００２５】（第２の実施形態）図４は、本発明の第２
の実施形態として、第１及び第２の受信系の各復調出力
を用いて、キャリア単位で選択ダイバーシチを行うＯＦ
ＤＭダイバーシチ受信装置の構成を示すブロック図であ
る。尚、図４において、図１と同一部分には同一符号を
付してその説明を省略し、ここでは異なる部分について
説明する。(Second Embodiment) FIG. 4 shows a second embodiment of the present invention.
As an embodiment of OF, OF which performs selective diversity on a carrier-by-carrier basis using each demodulated output of the first and second receiving systems
It is a block diagram which shows the structure of a DM diversity receiver. In FIG. 4, the same parts as those in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted. Here, different parts will be described.
【００２６】図４において、信頼性情報検出回路１８、
２６の出力は比較回路３０に供給される。比較回路３０
は、キャリア毎に第１及び第２の受信系の信頼性情報を
比較し、信頼性情報の大きい系統を選択するための制御
信号を出力する。一方の受信系のキャリアが妨害を受け
ている場合、その信頼性情報は０になっているので、結
果として妨害を受けていない系統が選択される。第１及
び第２の受信系の信頼性情報がともに０の場合は、どち
らを選択しても意味はないため、どちらか一方を選択す
る。In FIG. 4, the reliability information detection circuit 18,
The output of 26 is supplied to the comparison circuit 30. Comparison circuit 30
Outputs the control signal for comparing the reliability information of the first and second receiving systems for each carrier and selecting the system having the larger reliability information. When the carrier of one of the receiving systems is disturbed, the reliability information is 0, and as a result, the system that is not disturbed is selected. If the reliability information of both the first and second receiving systems is 0, it does not make sense to select either one, so one of them is selected.
【００２７】比較回路３０の出力は選択ダイバーシチ回
路３１のセレクタ３１１、３１２に供給される。これら
のセレクタ３１１、３１２には、それぞれ第１及び第２
の受信系の復調データ、信頼性情報が供給されており、
比較回路３０からの制御信号に基づいていずれか一方の
受信系の復調データ、信頼性情報を選択出力する。The output of the comparison circuit 30 is supplied to the selectors 311 and 312 of the selection diversity circuit 31. These selectors 311 and 312 have a first and a second, respectively.
Demodulation data and reliability information of the receiving system of
Based on the control signal from the comparison circuit 30, the demodulation data and reliability information of either one of the receiving systems are selectively output.
【００２８】上記の構成では、比較回路３０において、
一方の受信系が妨害を受けている場合には他方の受信系
を選択するように制御信号を生成しているため、妨害の
影響を除去した選択ダイバーシチが可能である。また、
両方ともに妨害を受けている場合は、選択ダイバーシチ
後の信頼性情報も０になるため、誤り訂正回路２９で消
失訂正を行うことが可能となる。In the above configuration, in the comparison circuit 30,
When one of the receiving systems is disturbed, the control signal is generated so as to select the other receiving system, so that the selection diversity without the influence of the disturbing is possible. Also,
When both are disturbed, the reliability information after the selection diversity is also 0, so that the error correction circuit 29 can perform erasure correction.
【００２９】以上により、本実施形態の構成によれば、
キャリア妨害の悪影響を受けることなくキャリア単位の
選択ダイバーシチを行うことができ、しかも各キャリア
の信頼性情報も選択して誤り訂正回路２９に供給するよ
うにしているので、誤り訂正の特性を向上させることが
できる。図１に示した合成ダイバーシチと比較すると、
効果は若干劣るが、回路構成が簡単になるというメリッ
トがある。As described above, according to the configuration of this embodiment,
Selective diversity can be performed on a carrier-by-carrier basis without being adversely affected by carrier interference, and reliability information of each carrier is also selected and supplied to the error correction circuit 29, so that error correction characteristics are improved. be able to. Compared with the synthetic diversity shown in FIG. 1,
The effect is slightly inferior, but there is an advantage that the circuit configuration becomes simple.
【００３０】（第３の実施形態）図５は本発明の第３の
実施形態として、第１の実施形態とは異なる信頼性情報
算出回路を用いたＯＦＤＭダイバーシチ受信装置の構成
を示すブロック図である。尚、図５において、図１と同
一部分には同一符号を付してその説明を省略し、ここで
は異なる部分について説明する。(Third Embodiment) FIG. 5 is a block diagram showing the configuration of an OFDM diversity receiver using a reliability information calculation circuit different from that of the first embodiment as a third embodiment of the present invention. is there. In FIG. 5, the same parts as those in FIG. 1 are designated by the same reference numerals, and the description thereof will be omitted. Here, different parts will be described.
【００３１】図５に示す第１、第２の受信系の信頼性算
出回路１８、２６において、しきい値算出回路１８３、
２６３でそれぞれ算出された分散の判定しきい値は、し
きい値選択回路３２に供給される。このしきい値選択回
路３２は、各受信系から供給されたしきい値を比較し、
小さい方を選択して出力する。信頼性検出回路１８、２
６のしきい値判定回路１８３、２６３は、しきい値選択
回路３２で選択されたしきい値を用いて各キャリアの分
散を判定する。In the reliability calculating circuits 18 and 26 of the first and second receiving systems shown in FIG. 5, the threshold calculating circuit 183,
The variance determination thresholds calculated in 263 are supplied to the threshold selection circuit 32. This threshold value selection circuit 32 compares the threshold values supplied from each receiving system,
Select the smaller one and output. Reliability detection circuit 18, 2
The threshold value judging circuits 183 and 263 of No. 6 judge the dispersion of each carrier using the threshold value selected by the threshold value selecting circuit 32.
【００３２】アンテナ障害などの原因で受信状態が劣化
した場合、全キャリアの分散値が増加し、これに伴い分
散判定のしきい値も大きくなる。すなわち、分散判定し
きい値は全キャリアの平均的な受信品質を示している。
したがって、本実施形態のように、第１及び第２の受信
系の分散判定しきい値の中から小さい方を選択して用い
ることにより、一方の受信系の受信状態が劣化した場合
でも、これを妨害とみなして除去することが可能とな
る。When the reception condition deteriorates due to an antenna failure or the like, the dispersion value of all carriers increases, and the threshold value for dispersion determination also increases accordingly. That is, the variance determination threshold indicates the average reception quality of all carriers.
Therefore, even if the reception state of one of the receiving systems is deteriorated by selecting and using the smaller one of the dispersion determination thresholds of the first and second receiving systems as in this embodiment, Can be considered as an obstacle and removed.
【００３３】（第４の実施形態）図６は本発明の第４の
実施形態として、第１、第３の実施形態とは異なる信頼
性情報算出回路を用いたＯＦＤＭダイバーシチ受信装置
の構成を示すブロック図である。尚、図６において、図
１と同一部分には同一符号を付してその説明を省略し、
ここでは異なる部分について説明する。(Fourth Embodiment) FIG. 6 shows, as a fourth embodiment of the present invention, a structure of an OFDM diversity receiver using a reliability information calculation circuit different from those of the first and third embodiments. It is a block diagram. Incidentally, in FIG. 6, the same parts as those in FIG.
Here, different parts will be described.
【００３４】図６に示す第１、第２の受信系の信頼性算
出回路１８、２６では、キャリアの分散検出、しきい値
算出を行わず、しきい値判定回路１８６、２６６によ
り、電力検出回路１８１、２６１で検出された各キャリ
アの受信電力を予め設定された所定のしきい値と比較
し、所定値よりも大きい場合は妨害を受けていると判定
するようにしている。The reliability calculation circuits 18 and 26 of the first and second reception systems shown in FIG. 6 do not perform carrier dispersion detection and threshold calculation, but the threshold determination circuits 186 and 266 detect power. The reception power of each carrier detected by the circuits 181 and 261 is compared with a predetermined threshold value set in advance, and if it is larger than the predetermined value, it is determined that the interference is occurring.
【００３５】本実施形態の構成によれば、図１に示した
第１の実施形態による分散検出を利用した妨害判定と比
較すると、妨害検出精度が劣るが、レベルの大きな妨害
を対象としたときに簡単な回路構成で妨害判定ができる
というメリットがある。According to the configuration of the present embodiment, the accuracy of the interference detection is inferior as compared with the interference determination using the distributed detection according to the first embodiment shown in FIG. The advantage is that interference can be determined with a simple circuit configuration.
【００３６】（変形例）なお、図５、図６に示す第３、
第４の実施形態は合成ダイバーシチの場合を説明するも
のであるが、選択ダイバーシチの場合でも同様に適用で
きることは明らかである。(Modification) It should be noted that the third and the third shown in FIGS.
Although the fourth embodiment describes the case of combined diversity, it is clear that it can be similarly applied to the case of selective diversity.
【００３７】また、上記の各実施形態においては、２系
統の復調データを用いてキャリア単位でダイバーシチを
行う場合の例を示したが、３系統以上のダイバーシチ受
信にも適用できることは明らかである。Further, in each of the above-described embodiments, an example is shown in which the demodulation data of two systems is used to perform diversity on a carrier-by-carrier basis, but it is clear that the present invention can also be applied to diversity reception of three or more systems.
【００３８】また、合成ダイバーシチの場合には、信頼
性算出回路１８、２６での信頼性判定において、しきい
値を段階的に設定して妨害波レベルに応じた判定値を求
めるようにし、この判定結果に基づいて各受信系に対す
る重み付け係数も段階的に設定することで、両受信系の
合成をより最適に行えるようになる。In the case of combined diversity, in the reliability judgment by the reliability calculation circuits 18 and 26, threshold values are set stepwise to obtain a judgment value according to the interference wave level. By setting the weighting coefficient for each receiving system stepwise based on the determination result, it becomes possible to more optimally combine both receiving systems.
【００３９】また、本発明は上記の実施形態に限定され
るものではなく、様々な変形が可能である。The present invention is not limited to the above embodiment, but various modifications can be made.
【００４０】以上、ＯＦＤＭのキャリア単位で受信電力
に応じて合成または選択ダイバーシチを行う受信装置に
ついて説明したが、図７（ａ）、（ｂ）に示す２系統の
受信電力の周波数分布から明らかなように、一般に２系
統の伝送路応答は異なるため、上記実施形態のように２
系統以上の復調信号を合成または選択することにより、
周波数選択性の伝送路歪みを大幅に改善することができ
る。また、移動受信時に生じる時間方向の変動も同様に
改善することができる。The receiving apparatus which performs the combining or the selective diversity according to the received power in the unit of OFDM carrier has been described above, but it is clear from the frequency distribution of the received power of the two systems shown in FIGS. 7 (a) and 7 (b). As described above, the transmission path responses of the two systems are generally different.
By synthesizing or selecting demodulated signals of system or higher,
Frequency selective transmission line distortion can be greatly improved. Further, the fluctuation in the time direction that occurs during mobile reception can be similarly improved.
【００４１】[0041]
【発明の効果】以上のように本発明によれば、特定のキ
ャリアが妨害を受けた場合でも、誤り訂正の特性が向上
するように効果的にダイバーシチを行うことのできるＯ
ＦＤＭダイバーシチ受信装置を提供することができる。As described above, according to the present invention, even if a specific carrier is disturbed, it is possible to effectively perform diversity so as to improve the error correction characteristic.
An FDM diversity receiver can be provided.
【図１】 本発明の第１の実施形態とするＯＦＤＭ受信
装置の構成を示すブロック図。FIG. 1 is a block diagram showing a configuration of an OFDM receiving apparatus according to a first embodiment of the present invention.
【図２】 第１の同実施形態に用いる分散検出回路の具
体的な構成を示すブロック図。FIG. 2 is a block diagram showing a specific configuration of a dispersion detection circuit used in the first embodiment.
【図３】 （ａ）、（ｂ）は、第１の実施形態におい
て、分散を用いた妨害検出の動作を説明する図。3A and 3B are diagrams illustrating an operation of interference detection using dispersion in the first embodiment.
【図４】 本発明の第２の実施形態とするＯＦＤＭ受信
装置の構成を示すブロック図。FIG. 4 is a block diagram showing a configuration of an OFDM receiver according to a second embodiment of the present invention.
【図５】 本発明の第３の実施形態とするＯＦＤＭ受信
装置の構成を示すブロック図。FIG. 5 is a block diagram showing a configuration of an OFDM receiving apparatus according to a third embodiment of the present invention.
【図６】 本発明の第４の実施形態とするＯＦＤＭ受信
装置の構成を示すブロック図。FIG. 6 is a block diagram showing a configuration of an OFDM receiver according to a fourth embodiment of the present invention.
【図７】 （ａ）、（ｂ）は、ＯＦＤＭキャリア単位の
ダイバーシチの動作を説明するための２系統の受信電力
の周波数分布を示す図。7A and 7B are diagrams showing frequency distributions of received powers of two systems for explaining an operation of diversity in OFDM carrier units.
１１，１９…アンテナ、１２，２０…チューナ、１３，
２１…Ａ／Ｄ変換器、１４，２２…ＡＧＣ回路、１５，
２３…ＩＱ復調回路、１６，２４…ＦＦＴ回路、１７，
２５…復調回路、１８，２６…信頼性情報算出回路、１
８１，２６１…電力検出回路、１８２，２６２…分散検
出回路、１８３，２６３…しきい値算出回路、１８４，
１８６，２６４，２６６…しきい値判定回路、１８５，
２６５…補正回路、２７…重み付け係数回路、２８…合
成ダイバーシチ回路、２８１，２８２，２８４，２８５
…乗算器、２８３，２８６…加算器、２９…誤り訂正回
路、３０…比較回路、３１…選択ダイバーシチ回路、３
１１，３１２…セレクタ、３２…しきい値選択回路、Ａ
１，Ａ３…硬判定回路、Ａ２，Ａ４…差分回路、Ａ５…
自乗和回路、Ａ６…積分回路。11, 19 ... Antenna, 12, 20 ... Tuner, 13,
21 ... A / D converter, 14, 22 ... AGC circuit, 15,
23 ... IQ demodulation circuit, 16, 24 ... FFT circuit, 17,
25 ... Demodulation circuit, 18, 26 ... Reliability information calculation circuit, 1
81, 261 ... Power detection circuit, 182, 262 ... Dispersion detection circuit, 183, 263 ... Threshold calculation circuit, 184
186, 264, 266 ... Threshold value judging circuit, 185
265 ... Correction circuit, 27 ... Weighting coefficient circuit, 28 ... Combining diversity circuit, 281, 282, 284, 285
... Multiplier, 283, 286 ... Adder, 29 ... Error correction circuit, 30 ... Comparison circuit, 31 ... Selection diversity circuit, 3
11, 312 ... Selector, 32 ... Threshold selection circuit, A
1, A3 ... Hard decision circuit, A2, A4 ... Difference circuit, A5 ...
Square sum circuit, A6 ... Integrator circuit.
───────────────────────────────────────────────────── フロントページの続き (56)参考文献 特開 平９−284191（ＪＰ，Ａ) 特開 平10−107714（ＪＰ，Ａ) 特開 平６−232793（ＪＰ，Ａ) 特開 平11−252040（ＪＰ，Ａ) (58)調査した分野(Int.Cl.7，ＤＢ名) H04J 11/00 H04B 7/08 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-9-284191 (JP, A) JP-A-10-107714 (JP, A) JP-A-6-232793 (JP, A) JP-A-11- 252040 (JP, A) (58) Fields investigated (Int.Cl. 7 , DB name) H04J 11/00 H04B 7/08
Claims (11)
独立してＯＦＤＭ（直交周波数分割多重）信号を受信
し、この受信信号を時間領域から周波数領域に変換して
キャリア毎の信号を取り出し、各キャリアに割り当てら
れている信号データを復調する複数のＯＦＤＭ受信・復
調手段と、 前記複数の受信系それぞれのＯＦＤＭ受信・復調手段で
得られる各キャリアの復調データを入力してキャリア単
位でダイバーシチ処理を行うダイバーシチ処理手段とを
備えるＯＦＤＭダイバーシチ受信装置において、 前記複数の受信系それぞれのＯＦＤＭ受信・復調手段で
得られる前記キャリア毎の復調データに及ぼされている
妨害の強度を判定し、この判定結果に基づいて前記復調
データの信頼性の度合を示す信頼性情報を前記キャリア
毎に求める信頼性情報取得手段と、 前記信頼性情報取得手段で得られる前記複数の受信系の
キャリア毎の信頼性情報に基づいて前記ダイバーシチ処
理手段でダイバーシチ処理するキャリアを制限するダイ
バーシチ処理制御手段とを具備することを特徴とするＯ
ＦＤＭダイバーシチ受信装置。1. An OFDM (Orthogonal Frequency Division Multiplexing) signal which is provided in each of a plurality of receiving systems and receives the signals independently of each other, converts the received signal from a time domain to a frequency domain, and extracts a signal for each carrier, A plurality of OFDM receiving / demodulating means for demodulating signal data assigned to each carrier, and demodulation data of each carrier obtained by the OFDM receiving / demodulating means of each of the plurality of receiving systems are input to perform diversity processing in carrier units. In an OFDM diversity receiving apparatus including a diversity processing means for performing, the strength of the interference exerted on the demodulated data for each carrier obtained by the OFDM receiving / demodulating means of each of the plurality of receiving systems is determined, and the result of this determination The reliability information indicating the degree of reliability of the demodulated data is calculated for each carrier based on And a diversity processing control means for limiting the carriers to be diversity-processed by the diversity processing means based on the reliability information for each carrier of the plurality of receiving systems obtained by the reliability information acquisition means. O characterized by
FDM diversity receiver.
得られる各キャリアの受信電力を検出する受信電力検出
部と、 前記複数の受信系それぞれのＯＦＤＭ受信・復調手段で
得られる各キャリアが受けている妨害の強度を判定する
妨害判定部と、 前記複数の受信系それぞれのＯＦＤＭ受信・復調手段で
得られる各キャリアの復調データについて、前記受信電
力検出部の検出結果及び前記妨害判定部の判定結果から
信頼性の度合を示す信頼性情報を算出する信頼性情報算
出部とを備えることを特徴とする請求項１記載のＯＦＤ
Ｍダイバーシチ受信装置。2. The reliability information acquisition means includes a reception power detection section for detecting reception power of each carrier obtained by the OFDM reception / demodulation means of each of the plurality of reception systems, and OFDM of each of the plurality of reception systems. An interference determination unit for determining the strength of interference received by each carrier obtained by the receiving / demodulating means, and the received power detection for demodulated data of each carrier obtained by the OFDM receiving / demodulating means of each of the plurality of receiving systems. 2. The OFD according to claim 1, further comprising: a reliability information calculation unit that calculates reliability information indicating a degree of reliability based on a detection result of a unit and a determination result of the disturbance determination unit.
M diversity receiver.
得られる各キャリアの復調データからキャリア毎の分散
値を検出する分散値検出手段と、 前記複数の受信系毎に、前記分散値検出手段で得られる
キャリア毎の分散値から妨害判定基準となる１以上のし
きい値を求めるしきい値算出手段と、 前記複数の受信系毎に、前記分散値検出手段で得られる
キャリア毎の分散値を前記しきい値算出手段で求められ
た１以上のしきい値と比較することで、各キャリアが受
けている妨害の強度を判定する判定手段とを備えること
を特徴とする請求項２記載のＯＦＤＭダイバーシチ受信
装置。Wherein the interference determination unit, for each of the plurality of receiving systems, the OFDM reception and detection for dispersion value detecting dispersion value of each carrier from the demodulated data of each carrier obtained <br/> the demodulation hand stage Means, threshold value calculating means for obtaining, for each of the plurality of receiving systems, one or more threshold values serving as an interference determination criterion from the dispersion value of each carrier obtained by the dispersion value detecting means, and the plurality of receiving systems. Each time, the dispersion value for each carrier obtained by the dispersion value detecting means is compared with one or more threshold values obtained by the threshold value calculating means to determine the strength of interference received by each carrier. The OFDM diversity receiver according to claim 2, further comprising:
得られる各キャリアの復調データからキャリア毎の分散
値を検出する分散値検出手段と、 前記複数の受信系毎に、前記分散値検出手段で得られる
キャリア毎の分散値を平均化し、受信系毎に得られた平
均値のうち、最小値を妨害判定基準となるしきい値とす
るしきい値算出手段と、 前記複数の受信系毎に、前記分散値検出手段で得られる
キャリア毎の分散値を前記しきい値算出手段で選定され
たしきい値と比較することで、各キャリアが受けている
妨害の強度を判定する判定手段とを備えることを特徴と
する請求項２記載のＯＦＤＭダイバーシチ受信装置。Wherein said interference determining unit for each of the plurality of receiving systems, the OFDM reception and detection for dispersion value detecting dispersion value of each carrier from the demodulated data of each carrier obtained <br/> the demodulation hand stage Means, for each of the plurality of receiving systems, averages the dispersion values for each carrier obtained by the dispersion value detecting means, and among the average values obtained for each receiving system, the minimum value serves as a threshold for interference determination. A threshold value calculating means for setting a value, and for each of the plurality of receiving systems, by comparing the dispersion value for each carrier obtained by the dispersion value detecting means with the threshold value selected by the threshold value calculating means. The OFDM diversity receiving apparatus according to claim 2, further comprising: a determining unit that determines the strength of the interference received by each carrier.
それぞれのＯＦＤＭ受信・復調手段で得られる各キャリ
アの復調データを硬判定することで２値の分散値を求め
ることを特徴とする請求項３または４記載のＯＦＤＭダ
イバーシチ受信装置。5. The dispersion value detecting means comprises a plurality of receiving systems.
Each OFDM diversity receiver according to claim 3 or 4, wherein the obtaining the variance value of the binary by hard decision demodulated data of each carrier obtained by the OFDM receiving and demodulating means.
それぞれのＯＦＤＭ受信・復調手段で得られる各キャリ
アの復調データを軟判定することで分散値を段階的に求
めることを特徴とする請求項３または４記載のＯＦＤＭ
ダイバーシチ受信装置。6. The dispersion value detecting means comprises a plurality of receiving systems.
5. The OFDM according to claim 3, wherein the dispersion value is obtained stepwise by softly judging demodulation data of each carrier obtained by each OFDM receiving / demodulating means.
Diversity receiver.
に、前記受信電力検出部で得られる各キャリアの受信電
力を予め設定されたしきい値と比較することで、各キャ
リアが受けている妨害の強度を判定することを特徴とす
る請求項２記載のＯＦＤＭダイバーシチ受信装置。7. The interference determination unit compares the reception power of each carrier obtained by the reception power detection unit with a preset threshold value for each of the plurality of reception systems, so that each carrier receives 3. The OFDM diversity receiver according to claim 2, wherein the strength of the generated interference is determined.
受信系それぞれのＯＦＤＭ受信・復調手段で得られる復
調データをキャリア単位で合成するものであり、 前記ダイバーシチ処理制御手段は、前記信頼性情報算出
手段で得られるキャリア単位の信頼性情報に基づいて前
記ダイバーシチ処理手段で合成される復調データの重み
付けを行うことを特徴とする請求項１記載のＯＦＤＭダ
イバーシチ受信装置。8. The diversity processing means synthesizes demodulated data obtained by the OFDM receiving / demodulating means of each of the plurality of receiving systems on a carrier-by-carrier basis, and the diversity processing controlling means calculates the reliability information. 2. The OFDM diversity receiver according to claim 1, wherein the demodulation data combined by the diversity processing means is weighted based on reliability information on a carrier basis obtained by the means.
受信系それぞれのＯＦＤＭ受信・復調手段で得られる復
調データをキャリア単位で選択するものであり、 前記ダイバーシチ処理制御手段は、前記信頼性情報算出
手段で得られるキャリア単位の信頼性情報に基づいて前
記ダイバーシチ処理手段で選択される復調データを指定
することを特徴とする請求項１記載のＯＦＤＭダイバー
シチ受信装置。9. The diversity processing means selects demodulated data obtained by the OFDM receiving / demodulating means of each of the plurality of receiving systems on a carrier-by-carrier basis, and the diversity processing control means calculates the reliability information. 2. The OFDM diversity receiving apparatus according to claim 1, wherein the demodulation data selected by the diversity processing means is designated based on the reliability information on a carrier basis obtained by the means.
理される復調データの誤り訂正を行う誤り訂正手段を備
え、 前記ダイバーシチ処理手段は、前記信頼性情報算出手段
で得られる複数の受信系のキャリア単位の信頼性情報を
ダイバーシチ処理し、 前記誤り訂正手段は、前記ダイバーシチ処理手段でダイ
バーシチ処理される信頼性情報に基づいて復調データの
消失訂正を行うことを特徴とする請求項１記載のＯＦＤ
Ｍダイバーシチ受信装置。10. An error correction means for correcting an error in demodulated data processed by the diversity processing means, wherein the diversity processing means is a unit of carrier of a plurality of receiving systems obtained by the reliability information calculating means. 2. The OFD according to claim 1, wherein the reliability information of the demodulation data is subjected to diversity processing, and the error correction means performs erasure correction of demodulated data based on the reliability information subjected to the diversity processing by the diversity processing means.
M diversity receiver.
それぞれ受信チャンネルを選局する選局手段を備え、互
いに同一のチャンネルを選局することを特徴とする請求
項１記載のＯＦＤＭダイバーシチ受信装置。11. The plurality of OFDM receiving / demodulating means,
2. The OFDM diversity receiving apparatus according to claim 1, further comprising tuning means for selecting a receiving channel, respectively, for selecting the same channel.
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP34048899A JP3389178B2 (en) | 1999-11-30 | 1999-11-30 | OFDM diversity receiver |
| SG200003137A SG115339A1 (en) | 1999-11-30 | 2000-06-06 | Ofdm diversity receiver |
| CNB001186019A CN1178416C (en) | 1999-11-30 | 2000-06-16 | Quadrature frequency division multiplex diversing receiver |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP34048899A JP3389178B2 (en) | 1999-11-30 | 1999-11-30 | OFDM diversity receiver |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JP2001156738A JP2001156738A (en) | 2001-06-08 |
| JP3389178B2 true JP3389178B2 (en) | 2003-03-24 |
Family
ID=18337456
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP34048899A Expired - Fee Related JP3389178B2 (en) | 1999-11-30 | 1999-11-30 | OFDM diversity receiver |
Country Status (3)
| Country | Link |
|---|---|
| JP (1) | JP3389178B2 (en) |
| CN (1) | CN1178416C (en) |
| SG (1) | SG115339A1 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| EP1689139A2 (en) | 2005-02-03 | 2006-08-09 | Matsushita Electric Industrial Co., Ltd. | Broadcast interference elimination in OFDM receiving systems |
| US7466645B2 (en) | 2004-12-21 | 2008-12-16 | Panasonic Corporation | OFDM signal receiving apparatus |
Families Citing this family (30)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3776716B2 (en) | 2000-11-17 | 2006-05-17 | 株式会社東芝 | Orthogonal frequency division multiplex transmission signal receiver |
| FR2835985B1 (en) * | 2002-02-13 | 2004-05-14 | Dibcom | MODULAR DEVICE FOR RECEIVING DIVERSITY OF A MODULATED SIGNAL |
| JP3538187B2 (en) | 2002-03-26 | 2004-06-14 | 株式会社東芝 | OFDM receiver and data demodulation method in OFDM receiver |
| JP2003333012A (en) | 2002-05-16 | 2003-11-21 | Matsushita Electric Ind Co Ltd | Device and method for diversity |
| FR2844407B1 (en) | 2002-09-05 | 2004-12-03 | Thomson Licensing Sa | TRANSMISSION CHANNEL SELECTION METHOD AND ANTENNA DIVERSITY SIGNAL RECEIVER |
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| US7310503B2 (en) | 2002-10-28 | 2007-12-18 | Mitsubishi Denki Kabushiki Kaisha | Diversity reception device and diversity reception method |
| KR100505694B1 (en) * | 2003-07-09 | 2005-08-02 | 삼성전자주식회사 | Apparatus for direct measurement of the channel state for the coded orthogonal frequency division multiplexing receiver and method thereof |
| JP4183613B2 (en) * | 2003-12-26 | 2008-11-19 | 三洋電機株式会社 | Receiving method and apparatus |
| JP4059227B2 (en) * | 2004-05-21 | 2008-03-12 | ソニー株式会社 | Demodulator |
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| KR20070067680A (en) * | 2004-09-10 | 2007-06-28 | 마쓰시다 일렉트릭 인더스트리얼 컴패니 리미티드 | Wireless communication apparatus and wireless communication method |
| KR20070052758A (en) * | 2004-09-17 | 2007-05-22 | 마츠시타 덴끼 산교 가부시키가이샤 | Transmission control frame generation device and transmission control device |
| JP4682684B2 (en) | 2005-04-28 | 2011-05-11 | パナソニック株式会社 | Digital signal receiver |
| US7474719B2 (en) * | 2005-06-06 | 2009-01-06 | Andrew Llc | Channel-dependent de-sensing of received signals |
| JP2007150468A (en) | 2005-11-24 | 2007-06-14 | Toshiba Corp | Diversity receiver |
| JP4697126B2 (en) * | 2006-11-21 | 2011-06-08 | 株式会社デンソー | Soft decision correction method, receiver, program |
| JP4816424B2 (en) * | 2006-11-21 | 2011-11-16 | 株式会社デンソー | Reception method, receiver, program |
| CN101083504B (en) * | 2007-07-23 | 2011-09-07 | 沖电气（新加坡）技术中心 | Demodulating equipment and its demodulating method |
| JP2009033497A (en) * | 2007-07-27 | 2009-02-12 | Hitachi Kokusai Electric Inc | Receiver |
| JP2009060177A (en) * | 2007-08-29 | 2009-03-19 | Kyocera Corp | Radio communication device and radio reception method |
| JP4551432B2 (en) * | 2007-09-28 | 2010-09-29 | 富士通テン株式会社 | Diversity receiving apparatus and diversity receiving method |
| JP4708400B2 (en) * | 2007-08-31 | 2011-06-22 | 富士通テン株式会社 | Diversity receiving apparatus, diversity receiving method, and digital television receiving apparatus |
| JP5433267B2 (en) * | 2009-03-19 | 2014-03-05 | 富士通テン株式会社 | In-vehicle device |
| JP5865083B2 (en) * | 2012-01-13 | 2016-02-17 | 日本放送協会 | Receiving apparatus and program |
| JP5865084B2 (en) * | 2012-01-13 | 2016-02-17 | 日本放送協会 | Receiving apparatus and program |
| WO2013128724A1 (en) | 2012-03-01 | 2013-09-06 | 三菱電機株式会社 | Reception device and reception method |
| JP5853809B2 (en) * | 2012-03-26 | 2016-02-09 | 沖電気工業株式会社 | Diversity receiver |
| JP5865773B2 (en) * | 2012-05-01 | 2016-02-17 | 富士通株式会社 | Receiving device and receiving method |
| JP6209990B2 (en) * | 2014-02-27 | 2017-10-11 | 富士通株式会社 | Receiver |
Family Cites Families (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| GB2308530B (en) * | 1995-12-21 | 2000-03-22 | Nokia Mobile Phones Ltd | Antenna selection control circuitry |
| JPH09238124A (en) * | 1996-03-01 | 1997-09-09 | Nec Corp | Diversity receiving method of high-speed data transmission system |
| JP3104617B2 (en) * | 1996-05-09 | 2000-10-30 | 日本電気株式会社 | Diversity receiving method and apparatus for high speed data transmission system in high speed mobile communication |
| JP3117415B2 (en) * | 1997-03-04 | 2000-12-11 | 株式会社次世代デジタルテレビジョン放送システム研究所 | Diversity receiving system and its transmitting device and receiving device |
| JP2904196B2 (en) * | 1997-07-16 | 1999-06-14 | 日本ビクター株式会社 | Diversity receiver for orthogonal frequency division multiplexed signal |
-
1999
- 1999-11-30 JP JP34048899A patent/JP3389178B2/en not_active Expired - Fee Related
-
2000
- 2000-06-06 SG SG200003137A patent/SG115339A1/en unknown
- 2000-06-16 CN CNB001186019A patent/CN1178416C/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7466645B2 (en) | 2004-12-21 | 2008-12-16 | Panasonic Corporation | OFDM signal receiving apparatus |
| EP1689139A2 (en) | 2005-02-03 | 2006-08-09 | Matsushita Electric Industrial Co., Ltd. | Broadcast interference elimination in OFDM receiving systems |
| EP2012487A2 (en) | 2005-02-03 | 2009-01-07 | Panasonic Corporation | Broadcast interference elimination in OFDM receiving systems |
Also Published As
| Publication number | Publication date |
|---|---|
| SG115339A1 (en) | 2005-10-28 |
| JP2001156738A (en) | 2001-06-08 |
| CN1178416C (en) | 2004-12-01 |
| CN1305277A (en) | 2001-07-25 |
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