JP2004007727A - High frequency switch - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a high frequency switch compatible with a duplex mode. <P>SOLUTION: The high frequency switch 21 roughly comprises: 10 main switching elements 22 to 31; a transmission side path circuit 40; a coupler 45; a low pass filter 50; and auxiliary switching elements 65 to 70 in shunt connection or the like. GaAs switches (MOS FET transistors) easily taking mutual synchronization for on / off control are adopted for the main switching elements 22 to 31. For example, in the case of connecting transmission / reception ports Rx, Tx to an antenna port ANT 1 at the same time, all or parts of the main switching elements 224, 27, a switching element 41 of the transmission path circuit 40, and the auxiliary switching elements 70, 65, 66, 68 are closed at the same time and the remaining switching elements are opened. <P>COPYRIGHT: (C)2004,JPO

Description

【００２７】
図２は、シングルモード１、すなわち、送信用ポートＴｘとアンテナ用ポートＡＮＴ１のみを繋げた場合の信号伝送経路を示すものである（図２の太線参照）。この場合は、主スイッチング素子３０と送信側パス回路４０のスイッチング素子４２と補助スイッチング素子６９，６５，６６，６８の全部もしくは一部をＯＮ状態にし、残りのスイッチング素子をＯＦＦ状態にする。基本的には、使用していないポートの補助スイッチング素子をＯＮ状態にする。スイッチング素子４１をＯＦＦ状態にすれば、信号はデュプレクサ用ポートＤＵＰ２の方に流れないと考えられるが、実際は、デュプレクサ用ポートＤＵＰ２の方に流れてしまう。そこで、補助スイッチング素子６９，６５，６６，６８をＯＮ状態にしておく。これにより、スイッチング素子４１をＯＦＦ状態にすることによるオープンと、補助スイッチング素子６９，６５，６６，６８をＯＮ状態にすることによるシャント接続との組み合わせで、確実にデュプレクサ用ポートＤＵＰ２への信号の流れを防止する。ただし、必ずしも全部の補助スイッチング素子６９，６５，６６，６８をＯＮ状態にしなくてもよい。なお、図２において、位相補正回路８１，８２は省略されている。以下、図３〜図１４においても同様である。
【００２８】
また、図３は、シングルモード２、すなわち、送信用ポートＴｘとアンテナ用ポートＡＮＴ２のみを繋げた場合の信号伝送経路を示すものである（図３の太線参照）。この場合、主スイッチング素子３１と送信側パス回路４０のスイッチング素子４２と補助スイッチング素子６９，６６，６７，６８の全部もしくは一部をＯＮ状態にし、残りのスイッチング素子をＯＦＦ状態にする。
【００２９】
さらに、図４は、シングルモード３、すなわち、送信用ポートＴｘと外部接続用ポートＥＸＴ１のみを繋げた場合の信号伝送経路を示すものである（図４の太線参照）。この場合、主スイッチング素子２９と送信側パス回路４０のスイッチング素子４２と補助スイッチング素子６９，６５，６６，６７の全部もしくは一部をＯＮ状態にし、残りのスイッチング素子をＯＦＦ状態にする。
【００３０】
以上のように、シングルモード１〜３の送信の際（言い換えると、パケット通信をしないとき）には、送信側パス回路４０のスイッチング素子４１，４２をＯＮ／ＯＦＦ制御して送信信号伝送経路をシングルモード系統にする。これにより、送信信号がデュプレクサ３５の送信側フィルタ３７を通らないようにすることができ、送信時の損失を抑えることができる。この結果、送信電力増幅器の消費電力を抑え、携帯電話の通話時間を長くすることができる。
【００３１】
図５は、シングルモード４、すなわち、受信用ポートＲｘとアンテナ用ポートＡＮＴ１のみを繋げた場合の信号伝送経路を示すものである（図５の太線参照）。この場合は、主スイッチング素子２４と補助スイッチング素子６９，７０，６５，６６，６８の全部もしくは一部をＯＮ状態にし、残りのスイッチング素子をＯＦＦ状態にする。
【００３２】
また、図６は、シングルモード５、すなわち、受信用ポートＲｘとアンテナ用ポートＡＮＴ２のみを繋げた場合の信号伝送経路を示すものである（図６の太線参照）。この場合、主スイッチング素子２２と補助スイッチング素子６９，７０，６６，６７，６８の全部もしくは一部をＯＮ状態にし、残りのスイッチング素子をＯＦＦ状態にする。
【００３３】
さらに、図７は、シングルモード６、すなわち、受信用ポートＲｘと外部接続用ポートＥＸＴ１のみを繋げた場合の信号伝送経路を示すものである（図７の太線参照）。この場合、主スイッチング素子２５と補助スイッチング素子６９，７０，６５，６６，６７の全部もしくは一部をＯＮ状態にし、残りのスイッチング素子をＯＦＦ状態にする。
【００３４】
さらに、図８は、シングルモード７、すなわち、受信用ポートＲｘと外部接続用ポートＥＸＴ２のみを繋げた場合の信号伝送経路を示すものである（図８の太線参照）。この場合、主スイッチング素子２３と補助スイッチング素子６９，７０，６５，６７，６８の全部もしくは一部をＯＮ状態にし、残りのスイッチング素子をＯＦＦ状態にする。
【００３５】
図９は、デュプレクスモード１、すなわち、送受信用ポートＲｘ，Ｔｘを同時に、アンテナ用ポートＡＮＴ１に繋げた場合の信号伝送経路を示すものである（図９の太線参照）。この場合、主スイッチング素子２４，２７と送信側パス回路４０のスイッチング素子４１と補助スイッチング素子７０，６５，６６，６８の全部もしくは一部を同時にＯＮ状態にし、残りのスイッチング素子をＯＦＦ状態にする。
【００３６】
図１０は、デュプレクスモード２、すなわち、受信用ポートＲｘをアンテナ用ポートＡＮＴ２に繋げると同時に、送信用ポートＴｘをアンテナ用ポートＡＮＴ１に繋げた場合の信号伝送経路を示すものである（図１０の太線参照）。この場合、主スイッチング素子２２，２７と送信側パス回路４０のスイッチング素子４１と補助スイッチング素子７０，６６，６８の全部もしくは一部を同時にＯＮ状態にし、残りのスイッチング素子をＯＦＦ状態にする。この場合、受信用ポートＲｘと送信用ポートＴｘはそれぞれ別のアンテナ用ポートＡＮＴ２，ＡＮＴ１に繋がっているため、Ｔｘ−Ｒｘ間のアイソレーションとして、１５〜２０ｄＢ程度ある空中のアイソレーションを使用可能である。このとき、デュプレクサ３５のＴｘ−Ｒｘ間のアイソレーション（減衰）特性を補助することが可能となり、デュプレクサ３５として、より損失の小さいフィルタ３６，３７を使用可能となる。
【００３７】
図１１は、デュプレクスモード３、すなわち、受信用ポートＲｘをアンテナ用ポートＡＮＴ１に繋げると同時に、送信用ポートＴｘをアンテナ用ポートＡＮＴ２に繋げた場合の信号伝送経路を示すものである（図１１の太線参照）。この場合、主スイッチング素子２４，２６と送信側パス回路４０のスイッチング素子４１と補助スイッチング素子７０，６６，６８の全部もしくは一部を同時にＯＮ状態にし、残りのスイッチング素子をＯＦＦ状態にする。この場合、受信用ポートＲｘと送信用ポートＴｘはそれぞれ別のアンテナ用ポートＡＮＴ１，ＡＮＴ２に繋がっているため、Ｔｘ−Ｒｘ間のアイソレーションとして、１５〜２０ｄＢ程度ある空中のアイソレーションを使用可能である。このとき、デュプレクサ３５のＴｘ−Ｒｘ間のアイソレーション（減衰）特性を補助することが可能となり、デュプレクサ３５として、より損失の小さいフィルタ３６，３７を使用可能となる。
【００３８】
図１２は、デュプレクスモード４、すなわち、送受信用ポートＲｘ，Ｔｘを同時に、アンテナ用ポートＡＮＴ２に繋げた場合の信号伝送経路を示すものである（図１２の太線参照）。この場合、主スイッチング素子２２，２６と送信側パス回路４０のスイッチング素子４１と補助スイッチング素子７０，６６，６７，６８の全部もしくは一部を同時にＯＮ状態にし、残りのスイッチング素子をＯＦＦ状態にする。
【００３９】
図１３は、デュプレクスモード５、すなわち、送受信用ポートＲｘ，Ｔｘを同時に、外部接続用ポートＥＸＴ１に繋げた場合の信号伝送経路を示すものである（図１３の太線参照）。この場合、主スイッチング素子２５，２８と送信側パス回路４０のスイッチング素子４１と補助スイッチング素子７０，６５，６６，６７の全部もしくは一部を同時にＯＮ状態にし、残りのスイッチング素子をＯＦＦ状態にする。
【００４０】
図１４は、デュプレクスモード６、すなわち、受信用ポートＲｘを外部接続用ポートＥＸＴ２に繋げると同時に、送信用ポートＴｘを外部接続用ポートＥＸＴ１に繋げた場合の信号伝送経路を示すものである（図１４の太線参照）。この場合、主スイッチング素子２３，２８と送信側パス回路４０のスイッチング素子４１と補助スイッチング素子７０，６５，６７の全部もしくは一部を同時にＯＮ状態にし、残りのスイッチング素子をＯＦＦ状態にする。
【００４１】
以上のように、デュプレクスモード１〜６は、主スイッチング素子２２〜３１などをＯＮ／ＯＦＦ制御することにより、送信用ポートＴｘおよび受信用ポートＲｘを、アンテナ用ポートＡＮＴ１，ＡＮＴ２や外部接続用ポートＥＸＴ１，ＥＸＴ２（同一ポートであってもよい）に同時に接続することができる。この結果、デュプレクスモードに対応可能な高周波スイッチ２１を得ることができる。
【００４２】
さらに、図１０に示したデュプレクスモード２および図１１に示したデュプレクスモード３のように接続した場合には、アンテナ素子６０，６１を介して相手側帯域（送信信号にとっては受信信号帯域、受信信号にとっては送信信号帯域）が妨害波となるが、１０〜１５ｄＢ程度の空中のアイソレーションにより、ある程度の減衰量を確保することができる。この減衰量の分だけ、デュプレクサ３５の減衰特性を軽減することができ、デュプレクサ３５の損失を改善することができる。そして、図１０に示したデュプレクスモード２のように接続した場合にも、同様の作用効果が得られる。
【００４３】
なお、本発明に係る高周波スイッチは前記実施形態に限定するものではなく、その要旨の範囲内で種々に変更することができる。例えば、図１に示した高周波スイッチ２１において、シャント接続された補助スイッチング素子６５〜７０やコンデンサＣ１〜Ｃ６、あるいは、カプラ４５やローパスフィルタ５０などを省いたものであってもよい。逆に、デュプレクサ３５や抵抗Ｒを内蔵した高周波スイッチであってもよい。
【００４４】
また、本発明に係る高周波スイッチは、複数の絶縁体層と、ローパスフィルタ５０のコンデンサ導体やコイル導体、あるいは、カプラ４５の主線路４６や副線路４７の導体などを積層して構成した積層体の表面に、送信用ポートＴｘや受信用ポートＲｘなどの各ポートを設けるとともに、主スイッチング素子２２〜３１のＧａＡｓスイッチを搭載することにより、積層構造のものを得ることができる。また、ＧａＡｓスイッチは複数の制御用端子を備えており、これらを制御するためのＩＣを搭載してもよい。この場合、この制御用ＩＣの入力は、簡略化された制御信号群ですむようになる。
【００４５】
【発明の効果】
以上の説明で明らかなように、本発明によれば、送信用ポートおよび受信用ポートを、アンテナ用ポートや外部接続用ポートに同時に接続することができる。この結果、デュプレクスモードに対応可能な高周波スイッチを得ることができる。さらに、少なくとも一つの信号伝送経路に補助スイッチング素子をシャント接続することにより、主スイッチング素子がＯＦＦ時の負荷変動を防止するとともに、主スイッチング素子がＯＦＦ時のアイソレーション特性の劣化を防止することができる。
【図面の簡単な説明】
【図１】本発明に係る高周波スイッチの一実施形態を示す電気回路図。
【図２】図１に示した高周波スイッチの動作を説明するための電気回路図。
【図３】図１に示した高周波スイッチの別の動作を説明するための電気回路図。
【図４】図１に示した高周波スイッチのさらに別の動作を説明するための電気回路図。
【図５】図１に示した高周波スイッチのさらに別の動作を説明するための電気回路図。
【図６】図１に示した高周波スイッチのさらに別の動作を説明するための電気回路図。
【図７】図１に示した高周波スイッチのさらに別の動作を説明するための電気回路図。
【図８】図１に示した高周波スイッチのさらに別の動作を説明するための電気回路図。
【図９】図１に示した高周波スイッチのさらに別の動作を説明するための電気回路図。
【図１０】図１に示した高周波スイッチのさらに別の動作を説明するための電気回路図。
【図１１】図１に示した高周波スイッチのさらに別の動作を説明するための電気回路図。
【図１２】図１に示した高周波スイッチのさらに別の動作を説明するための電気回路図。
【図１３】図１に示した高周波スイッチのさらに別の動作を説明するための電気回路図。
【図１４】図１に示した高周波スイッチのさらに別の動作を説明するための電気回路図。
【図１５】従来の高周波スイッチを示す電気回路図。
【符号の説明】
２１…高周波スイッチ
２２〜３１…主スイッチング素子
４０…送信側パス回路
４１，４２…スイッチング素子
６５〜７０…補助スイッチング素子
Ｒｘ…受信用ポート
Ｔｘ…送信用ポート
ＡＮＴ１，ＡＮＴ２…アンテナ用ポート
ＥＸＴ１，ＥＸＴ２…外部接続用ポート[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a high-frequency switch, and particularly to a high-frequency switch used by being incorporated in a mobile communication device such as a mobile phone.
[0002]
[Prior art]
Conventionally, as a high-frequency switch corresponding to antenna diversity, the one shown in FIG. 15 is known. This high-frequency switch 1 includes six switching elements 2 to 7. The transmission port Tx of the high-frequency switch 1 is electrically connected to the antenna port ANT1 via the switching element 6 and electrically connected to the external connection port EXT1 via the switching element 7. Similarly, the reception port Rx is electrically connected to the antenna port ANT2, the external connection port EXT2, the antenna port ANT1, and the external connection port EXT1 via the switching elements 2, 3, 4, and 5, respectively. ing. The antenna ports ANT1 and ANT2 are electrically connected to the antenna elements 10 and 11, respectively.
[0003]
[Problems to be solved by the invention]
In the high-frequency switch 1, the transmission port Tx is connected to the antenna port ANT1 or the external connection port EXT1, or the reception port Rx is connected to the antenna port by turning on / off the switching elements 2 to 7, respectively. ANT1 and ANT2 or external connection ports EXT1 and EXT2. However, since the conventional high-frequency switch 1 is used in a TDMA system, when connecting between the antenna ports ANT1 and ANT2 or the external connection ports EXT1 and EXT2 and the transmission / reception ports Tx and Rx, one of them is used. This is a configuration in which only one signal transmission path is connected, that is, a so-called single mode configuration. For this reason, the conventional high-frequency switch 1 is in a duplex (simultaneous transmission / reception) mode in which both the transmission port Tx and the reception port Rx are simultaneously connected to the antenna ports ANT1 and ANT2 and the external connection ports EXT1 and EXT2. Could not respond.
[0004]
Further, in PDC (Personal Digital Cellular) packet communication, which has been receiving particular attention in recent years, it is expected that the amount of data at the time of reception will be enormous. Therefore, it is necessary to operate the mobile phone in a duplex (simultaneous transmission / reception) mode in which reception is performed simultaneously with transmission in order to increase the amount of transmission at the time of reception. However, as described above, the conventional high-frequency switch 1 has a configuration in which only one of the signal transmission paths is connected, and thus cannot support a duplex mode in which it is necessary to connect two signal transmission paths at the same time. Was.
[0005]
Therefore, an object of the present invention is to provide a high-frequency switch capable of supporting a duplex mode.
[0006]
[Means and Actions for Solving the Problems]
In order to achieve the above object, the high-frequency switch according to the present invention,
(A) At least two signal transmission paths are provided between at least one of the antenna port and the external connection port and at least one of the transmission port and the reception port ,
(B) each of the at least two signal transmission paths includes at least one main switching element, and at least one of the signal transmission paths further includes at least one shunt-connected auxiliary switching element;
(C) synchronizing ON / OFF of at least two main switching elements and at least one auxiliary switching element,
(D) when the main switching element of the signal transmission path in which the auxiliary switching element is shunt-connected is in the ON state, the auxiliary switching element is turned OFF;
(E) when the main switching element of the signal transmission path to which the auxiliary switching element is shunt-connected is in the OFF state, the auxiliary switching element is configured to be in the ON state;
It is characterized by.
[0007]
Further, the high-frequency switch according to the present invention,
(F) At least two signal transmission paths are provided between at least one of the antenna port and the external connection port and at least one of the transmission port and the reception port. ,
(G) at least two signal transmission paths each including at least one main switching element and at least one shunt-connected auxiliary switching element;
(H) synchronizing ON / OFF of at least two main switching elements and at least two auxiliary switching elements,
(I) when the main switching element of the signal transmission path in which the auxiliary switching element is shunt-connected is in the ON state, the auxiliary switching element is turned OFF;
(J) when the main switching element of the signal transmission path to which the auxiliary switching element is shunt-connected is in the OFF state, the auxiliary switching element is configured to be in the ON state;
It is characterized by.
[0008]
With the above configuration, the transmission port and the reception port can be simultaneously connected to the antenna port and the external connection port, and a high-frequency switch compatible with the duplex (simultaneous transmission / reception) mode can be obtained. Further, the auxiliary switching element prevents load fluctuation when the main switching element is turned off and prevents deterioration of isolation characteristics when the main switching element is turned off.
[0009]
At least one of the at least two signal transmission paths may have a plurality of shunt-connected auxiliary switching elements. Specifically, for example, as shown in FIG. 2, in the case of a signal transmission path connecting the transmission port Tx and the antenna port ANT1, even if it has two shunt-connected auxiliary switching elements 67 and 70, Good.
[0010]
Also, at least one of the at least two signal transmission paths may have a plurality of main switching elements, and one of the auxiliary switching elements may be connected between the plurality of main switching elements. . Specifically, for example, as shown in FIG. 2, in the case of a signal transmission path connecting the transmission port Tx and the antenna port ANT1, a shunt connection is provided between the main switching element 30 and the main switching element 42. An auxiliary switching element 70 may be provided.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of a high-frequency switch according to the present invention will be described with reference to the accompanying drawings.
[0012]
As shown in FIG. 1, the high-frequency switch 21 corresponding to the antenna diversity is substantially shunt-connected to ten main switching elements 22 to 31, a transmission-side path circuit 40, a coupler 45, and a low-pass filter 50. It is composed of auxiliary switching elements 65 to 70 and the like.
[0013]
As the main switching elements 22 to 31, GaAs switches (MOS FET transistors) are used, which facilitate synchronization of ON / OFF control with each other. One end of the main switching element 22 is connected to the antenna port ANT2, one end of the main switching element 23 is connected to the external connection port EXT2, one end of the main switching element 24 is connected to the antenna port ANT1, and the main switching element 25 is connected. Is connected to an external connection port EXT1 via a low-pass filter 50. The other end of each of the main switching elements 22 to 25 is connected to the reception port Rx.
[0014]
One end of the main switching element 26 is connected to the antenna port ANT2, one end of the main switching element 27 is connected to the antenna port ANT1, and one end of the main switching element 28 is connected to the external connection port EXT1 via the low-pass filter 50. Have been. The other ends of the main switching elements 26 to 28 are connected to a duplexer port DUP1.
[0015]
One end of the main switching element 29 is connected to the external connection port EXT1 via the low-pass filter 50, one end of the main switching element 30 is connected to the antenna port ANT1, and one end of the main switching element 31 is connected to the antenna port ANT2. Have been. The other end of each of the main switching elements 29 to 31 is connected to the transmission port Tx via the transmission-side path circuit 40 and the coupler 45.
[0016]
Between the ports ANT1, ANT2, EXT1, and EXT2 and the main switching elements 22 to 31, a series circuit of auxiliary switching elements 65 to 70 and capacitor elements C1 to C6 is shunt-connected, respectively. The auxiliary switching elements 65 to 70 operate in conjunction with the main switching elements 22 to 31 and the switching elements 41 and 42 of the transmission-side path circuit 40 connected to the shunt-connected signal transmission paths. These shunt-connected series circuits prevent load fluctuations when the main switching elements 22 to 31 and the like are OFF, and also prevent deterioration of isolation characteristics.
[0017]
The receiving port Rx is connected to the receiving filter 36 of the duplexer 35 as a separate component, and the transmitting filter 37 of the duplexer 35 is connected between the duplexer ports DUP1 and DUP2. Note that instead of using one duplexer 35, two filters may be used in combination.
[0018]
The transmission-side path circuit 40 has two switching elements 41 and 42 connected in an L-shape. One end of the switching element 41 is connected to the duplexer port DUP2, and one end of the switching element 42 is connected to the main switching elements 29 to 31. The other ends of the switching elements 41 and 42 are connected to a transmission port Tx via a coupler 45. The transmission-side path circuit 40 is used to divide a transmission signal transmission path into two paths, that is, a single mode path and a duplex mode path.
[0019]
That is, as described later in detail, by turning the switching element 41 OFF and the switching element 42 ON, the transmission signal transmission path becomes a single mode system. In this case, the high-frequency switch 21 is used in a single mode configuration, in other words, the transmission / reception ports Tx and Rx are connected to only one signal transmission path with the antenna ports ANT1 and ANT2 and the external connection ports EXT1 and EXT2. In this case, the transmission signal does not pass through the transmission filter of the duplexer, so that transmission loss can be suppressed. On the other hand, when the switching element 41 is turned on and the switching element 42 is turned off, the transmission signal transmission path becomes a duplex mode system. In this case, the high-frequency switch 21 has a duplex mode configuration, in other words, a configuration in which both the transmission port Tx and the reception port Rx are simultaneously connected to one of the antenna ports ANT1 and ANT2 and the external connection ports EXT1 and EXT2. become.
[0020]
The coupler 45 includes a main line 46 and a sub line 47 electromagnetically coupled to the main line 46. The main line 46 is connected between the transmission port Tx and the transmission-side path circuit 40. One end of the sub line 47 is terminated by a resistor R via a port P, and the other end is connected to a detection port DET via a capacitor C8 and two Schottky diodes D1 and D2.
[0021]
The coupler 45 and the Schottky diodes D1 and D2 constitute a power amount detection circuit for power feedback to the transmission power amplifier. That is, the transmission signal output from the transmission power amplifier (not shown) is transmitted to the main line 46 of the coupler 45 via the transmission port Tx. The sub-line 47 is coupled to the transmission signal transmitted to the main line 46, takes out an output proportional thereto (power of -10 to -20 dBc of the transmission signal), and outputs an automatic gain control circuit through the detection port DET. (Not shown). The automatic gain control circuit monitors the output taken from the sub line 47 and controls the gain of the transmission power amplifier.
[0022]
The low-pass filter 50 is connected between the main switching element 28 and the external connection port EXT1. The low-pass filter 50 is not always necessary, and may be omitted depending on the specifications. Further, the low-pass filter may be connected between the external connection port EXT2 and the antenna ports ANT1 and ANT2 and the main switching elements 23, 27 and 22, respectively.
[0023]
The reception-side phase correction circuit 81 is connected between the reception port Rx and the main switching elements 22 to 25. The transmission-side phase correction circuit 82 is connected between the transmission port Tx (more specifically, the duplexer port DUP1) and the main switching elements 26 to 28. Each of the phase correction circuits 81 and 82 is configured by a distributed constant type circuit formed by a transmission line, a lumped constant type circuit formed by combining an inductor and a capacitor, or a delay line. Further, a phase correction circuit may be appropriately provided at the position shown in FIG.
[0024]
Next, transmission and reception using the high-frequency switch 21 will be described. As shown in FIG. 1, the high-frequency switch 21 has a main antenna element 60 and a sub-antenna (built-in antenna) element 61 connected to antenna ports ANT1 and ANT2, respectively, and a data transmission device connected to external connection ports EXT1 and EXT2, respectively. (Not shown) or the like is connected. On the other hand, a reception circuit (not shown) of the PDC 1500 (packet) is connected to the reception port Rx of the high-frequency switch 21 via the reception filter 36 of the duplexer 35, and the transmission port Tx is connected to the PDC 1500 (packet). A transmission circuit (not shown) is connected.
[0025]
As shown in Table 1, the high-frequency switch 21 controls a signal transmission path of a total of 13 modes of 7 single mode and 6 duplex mode by ON / OFF control of the switching elements 22 to 31, 41, 42 and the like. Have. Note that the conventional high-frequency switch 1 shown in FIG. 15 can obtain only signal transmission paths of a total of six modes of single modes 1, 3, 4, 5, 6, and 7 in Table 1.
[0026]
[Table 1]

[0027]
FIG. 2 shows a signal transmission path in the single mode 1, that is, when only the transmission port Tx and the antenna port ANT1 are connected (see the thick line in FIG. 2). In this case, all or part of the main switching element 30, the switching element 42 of the transmission-side path circuit 40, and the auxiliary switching elements 69, 65, 66, 68 are turned on, and the remaining switching elements are turned off. Basically, the auxiliary switching elements of unused ports are turned on. If the switching element 41 is turned off, it is considered that the signal does not flow toward the duplexer port DUP2, but actually, the signal flows toward the duplexer port DUP2. Therefore, the auxiliary switching elements 69, 65, 66, 68 are turned on. Thus, the combination of the opening by turning the switching element 41 OFF and the shunt connection by turning the auxiliary switching elements 69, 65, 66, 68 ON ensures the transmission of the signal to the duplexer port DUP2. Prevent flow. However, not all of the auxiliary switching elements 69, 65, 66, 68 need to be turned on. In FIG. 2, the phase correction circuits 81 and 82 are omitted. Hereinafter, the same applies to FIGS. 3 to 14.
[0028]
FIG. 3 shows a signal transmission path in the single mode 2, that is, when only the transmission port Tx and the antenna port ANT2 are connected (see the thick line in FIG. 3). In this case, all or a part of the main switching element 31, the switching element 42 of the transmission-side path circuit 40, and the auxiliary switching elements 69, 66, 67, 68 are turned on, and the remaining switching elements are turned off.
[0029]
FIG. 4 shows a signal transmission path in the single mode 3, that is, when only the transmission port Tx and the external connection port EXT1 are connected (see the thick line in FIG. 4). In this case, all or a part of the main switching element 29, the switching element 42 of the transmission-side path circuit 40, and the auxiliary switching elements 69, 65, 66, 67 are turned on, and the remaining switching elements are turned off.
[0030]
As described above, at the time of transmission in the single mode 1 to 3 (in other words, when packet communication is not performed), the switching elements 41 and 42 of the transmission-side path circuit 40 are ON / OFF controlled to change the transmission signal transmission path. Use a single mode system. As a result, the transmission signal can be prevented from passing through the transmission filter 37 of the duplexer 35, and the transmission loss can be suppressed. As a result, it is possible to suppress the power consumption of the transmission power amplifier and extend the talk time of the mobile phone.
[0031]
FIG. 5 shows a signal transmission path in the single mode 4, that is, when only the reception port Rx and the antenna port ANT1 are connected (see a thick line in FIG. 5). In this case, all or a part of the main switching element 24 and the auxiliary switching elements 69, 70, 65, 66, 68 are turned on, and the remaining switching elements are turned off.
[0032]
FIG. 6 shows a signal transmission path in the single mode 5, that is, when only the reception port Rx and the antenna port ANT2 are connected (see the thick line in FIG. 6). In this case, all or a part of the main switching element 22 and the auxiliary switching elements 69, 70, 66, 67, 68 are turned on, and the remaining switching elements are turned off.
[0033]
FIG. 7 shows a signal transmission path in the single mode 6, that is, when only the reception port Rx and the external connection port EXT1 are connected (see the thick line in FIG. 7). In this case, all or a part of the main switching element 25 and the auxiliary switching elements 69, 70, 65, 66, 67 are turned on, and the remaining switching elements are turned off.
[0034]
FIG. 8 shows a signal transmission path in the single mode 7, that is, when only the reception port Rx and the external connection port EXT2 are connected (see a thick line in FIG. 8). In this case, all or a part of the main switching element 23 and the auxiliary switching elements 69, 70, 65, 67, 68 are turned on, and the remaining switching elements are turned off.
[0035]
FIG. 9 shows a signal transmission path in the duplex mode 1, that is, when the transmission / reception ports Rx and Tx are simultaneously connected to the antenna port ANT1 (see the thick line in FIG. 9). In this case, all or a part of the main switching elements 24, 27, the switching element 41 of the transmission-side path circuit 40, and the auxiliary switching elements 70, 65, 66, 68 are simultaneously turned on, and the remaining switching elements are turned off. .
[0036]
FIG. 10 shows a signal transmission path in the duplex mode 2, that is, when the reception port Rx is connected to the antenna port ANT2 and the transmission port Tx is connected to the antenna port ANT1 (see FIG. 10). Bold line). In this case, all or a part of the main switching elements 22 and 27, the switching element 41 of the transmission-side path circuit 40, and the auxiliary switching elements 70, 66, and 68 are simultaneously turned on, and the remaining switching elements are turned off. In this case, since the reception port Rx and the transmission port Tx are connected to different antenna ports ANT2 and ANT1, respectively, an air isolation of about 15 to 20 dB can be used as the isolation between Tx and Rx. is there. At this time, the isolation (attenuation) characteristics between Tx and Rx of the duplexer 35 can be assisted, and filters 36 and 37 with smaller loss can be used as the duplexer 35.
[0037]
FIG. 11 shows a signal transmission path in the duplex mode 3, that is, when the reception port Rx is connected to the antenna port ANT1 and the transmission port Tx is connected to the antenna port ANT2 (see FIG. 11). Bold line). In this case, all or a part of the main switching elements 24, 26, the switching element 41 of the transmission-side path circuit 40, and the auxiliary switching elements 70, 66, 68 are simultaneously turned on, and the remaining switching elements are turned off. In this case, the reception port Rx and the transmission port Tx are connected to different antenna ports ANT1 and ANT2, respectively, so that air isolation of about 15 to 20 dB can be used as the isolation between Tx and Rx. is there. At this time, the isolation (attenuation) characteristics between Tx and Rx of the duplexer 35 can be assisted, and filters 36 and 37 with smaller loss can be used as the duplexer 35.
[0038]
FIG. 12 shows a signal transmission path in the duplex mode 4, that is, when the transmission / reception ports Rx and Tx are simultaneously connected to the antenna port ANT2 (see the thick line in FIG. 12). In this case, all or a part of the main switching elements 22 and 26, the switching element 41 of the transmission-side path circuit 40, and the auxiliary switching elements 70, 66, 67 and 68 are simultaneously turned on, and the remaining switching elements are turned off. .
[0039]
FIG. 13 shows a signal transmission path in the duplex mode 5, that is, when the transmission / reception ports Rx and Tx are simultaneously connected to the external connection port EXT1 (see a thick line in FIG. 13). In this case, all or a part of the main switching elements 25 and 28, the switching element 41 of the transmission-side path circuit 40, and the auxiliary switching elements 70, 65, 66, and 67 are simultaneously turned on, and the remaining switching elements are turned off. .
[0040]
FIG. 14 shows a signal transmission path in the duplex mode 6, that is, when the reception port Rx is connected to the external connection port EXT2 and the transmission port Tx is connected to the external connection port EXT1. 14 bold line). In this case, all or a part of the main switching elements 23, 28, the switching element 41 of the transmission side path circuit 40, and the auxiliary switching elements 70, 65, 67 are simultaneously turned on, and the remaining switching elements are turned off.
[0041]
As described above, in the duplex modes 1 to 6, by controlling ON / OFF of the main switching elements 22 to 31 and the like, the transmission port Tx and the reception port Rx are set to the antenna ports ANT1 and ANT2 and the external connection ports. EXT1 and EXT2 (may be the same port) can be connected simultaneously. As a result, the high-frequency switch 21 capable of supporting the duplex mode can be obtained.
[0042]
Further, when the connection is made as in the duplex mode 2 shown in FIG. 10 and the duplex mode 3 shown in FIG. 11, the other party's band (for the transmission signal, the reception signal band, the reception signal However, a certain amount of attenuation can be ensured by air isolation of about 10 to 15 dB. The attenuation characteristic of the duplexer 35 can be reduced by the amount of the attenuation, and the loss of the duplexer 35 can be improved. Similar effects can be obtained when the connection is made as in the duplex mode 2 shown in FIG.
[0043]
The high-frequency switch according to the present invention is not limited to the above embodiment, but can be variously modified within the scope of the gist. For example, in the high-frequency switch 21 shown in FIG. 1, the shunt-connected auxiliary switching elements 65 to 70 and the capacitors C1 to C6, or the coupler 45 and the low-pass filter 50 may be omitted. Conversely, a high-frequency switch including the duplexer 35 and the resistor R may be used.
[0044]
Further, the high-frequency switch according to the present invention is a laminated body formed by laminating a plurality of insulator layers, a capacitor conductor and a coil conductor of the low-pass filter 50, a conductor of the main line 46 and the sub-line 47 of the coupler 45, and the like. By providing each port such as the transmission port Tx and the reception port Rx on the surface of the device and mounting the GaAs switches of the main switching elements 22 to 31, a laminated structure can be obtained. Further, the GaAs switch has a plurality of control terminals, and an IC for controlling these terminals may be mounted. In this case, the input of the control IC only requires a simplified control signal group.
[0045]
【The invention's effect】
As apparent from the above description, according to the present invention, the transmission port and the reception port can be simultaneously connected to the antenna port and the external connection port. As a result, a high-frequency switch capable of supporting the duplex mode can be obtained. Furthermore, by shunt-connecting the auxiliary switching element to at least one signal transmission path, load fluctuation when the main switching element is OFF can be prevented, and deterioration of isolation characteristics when the main switching element is OFF can be prevented. it can.
[Brief description of the drawings]
FIG. 1 is an electric circuit diagram showing an embodiment of a high-frequency switch according to the present invention.
FIG. 2 is an electric circuit diagram for explaining the operation of the high-frequency switch shown in FIG.
FIG. 3 is an electric circuit diagram for explaining another operation of the high-frequency switch shown in FIG. 1;
FIG. 4 is an electric circuit diagram for explaining still another operation of the high-frequency switch shown in FIG. 1;
FIG. 5 is an electric circuit diagram for explaining still another operation of the high-frequency switch shown in FIG. 1;
FIG. 6 is an electric circuit diagram for explaining still another operation of the high-frequency switch shown in FIG. 1;
FIG. 7 is an electric circuit diagram for explaining still another operation of the high-frequency switch shown in FIG. 1;
FIG. 8 is an electric circuit diagram for explaining still another operation of the high-frequency switch shown in FIG. 1;
FIG. 9 is an electric circuit diagram for explaining still another operation of the high-frequency switch shown in FIG. 1;
FIG. 10 is an electric circuit diagram for explaining still another operation of the high-frequency switch shown in FIG. 1;
11 is an electric circuit diagram for explaining still another operation of the high-frequency switch shown in FIG.
FIG. 12 is an electric circuit diagram for explaining still another operation of the high-frequency switch shown in FIG. 1;
FIG. 13 is an electric circuit diagram for explaining still another operation of the high-frequency switch shown in FIG. 1;
FIG. 14 is an electric circuit diagram for explaining still another operation of the high-frequency switch shown in FIG. 1;
FIG. 15 is an electric circuit diagram showing a conventional high-frequency switch.
[Explanation of symbols]
21 ... High frequency switch
22-31 ... Main switching element
40 ... transmission side path circuit
41, 42 ... switching element
65-70 ... Auxiliary switching element
Rx ... Reception port
Tx: Transmission port
ANT1, ANT2 ... Antenna port
EXT1, EXT2 ... Port for external connection

Claims (4)

At least two signal transmission paths between the antenna port and at least one of the external connection ports and at least one of the transmission port and the reception port,
The at least two signal transmission paths each include at least one main switching element, of which at least one signal transmission path further includes at least one shunt-connected auxiliary switching element,
Synchronizing ON / OFF of at least two of the main switching elements and at least one of the auxiliary switching elements,
When the main switching element of the signal transmission path in which the auxiliary switching element is shunt-connected is in an ON state, the auxiliary switching element is turned OFF.
When the main switching element of the signal transmission path in which the auxiliary switching element is shunt-connected is in an OFF state, the auxiliary switching element is configured to turn on the auxiliary switching element.
A high frequency switch. At least two signal transmission paths between the antenna port and at least one of the external connection ports and at least one of the transmission port and the reception port,
The at least two signal transmission paths each include at least one main switching element, and each include at least one auxiliary switching element that is shunt-connected,
Synchronizing ON / OFF of at least two main switching elements and at least two auxiliary switching elements,
When the main switching element of the signal transmission path in which the auxiliary switching element is shunt-connected is in an ON state, the auxiliary switching element is turned OFF.
When the main switching element of the signal transmission path in which the auxiliary switching element is shunt-connected is in an OFF state, the auxiliary switching element is configured to turn on the auxiliary switching element.
A high frequency switch. The high-frequency switch according to claim 1, wherein at least one of the at least two signal transmission paths includes a plurality of the shunt-connected auxiliary switching elements. 4. . At least one of the at least two signal transmission paths has a plurality of the main switching elements, and one of the auxiliary switching elements is connected between the plurality of main switching elements. The high-frequency switch according to any one of claims 1 to 3, characterized in that:

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