Abstract:
A system includes a transmit filter (160) in a transmit path to couple to an antenna (120) and pass signals in a transmit band. A receive filter (155) is disposed in a receive path to couple to the antenna and to the transmit filter to pass signals in a receive band different from the transmit band. An enhanced frequency variable impedance (145) is used to provide isolation between signals in the transmit and receive bands on the receive path. A phase and magnitude controlled feedback path can also be used to cancel transmit signals in the receive path.
Abstract:
A method of offsetting a mismatch due user interaction when handling a portable wireless terminal in which antenna matching is changed from inductive matching to capacitive matching in response to a reactance change exceeding a threshold level and vice versa when an opposite change is detected. An antenna interface module (44) is coupled between a RF output or input stage (25 or 33) and an antenna (48 or 50). The antenna interface module includes first and second switches (SW1/1, SW1/2 or SW2/1, SW2/2), a first matching circuit including an inductive reactance (68 or 96) coupled between the power amplifier and the first switch and a second matching circuit including a capacitive reactance (68 or 92) is coupled between the RF output or input stage and the second switch (SW1/1 or SW2/1 ). A reactance threshold detector (54 or 56) determines if the reactance change traverses a predetermined threshold value and causes the first and second switches to be actuated so that the matching changes from inductive to capacitive or vice versa.
Abstract:
In an active antenna system, two or more amplification chains are contained on one integrated circuit substrate or in one hybrid circuit. The amplification chains can be connected to at least one of a plurality of radiating elements. The integrated circuit or hybrid circuit can be incorporated into an active antenna connector, which can be electrically connected to a radiating element or a receiver system, for example. A first integrated circuit or hybrid circuit can be exchanged with a second integrated circuit or hybrid circuit in a connector to adjust properties of an active antenna system.
Abstract:
A radio base station (20) comprises an antenna (22); a first power amplifier (24i) configured to receive a first carrier signal; a second power amplifier (242) configured to receive a second carrier signal; and a combiner (30). The combiner (30) is configured to apply a power imbalanced combined signal to the antenna. The power unbalanced combined signal has a power imbalance between a first power level of the first carrier signal and a second power level of the second carrier signal as transmitted from the antenna (22).
Abstract:
A filter arrangement (EFM) comprises a first terminal (T1) arranged for handling duplex radio antenna feeder signals for at least two transceiver modules (10, 20), a second terminal (T2) arranged for handling at least duplex signals for a first transceiver module (10), a third terminal (T3) arranged for outputting a first multi carrier power amplifier system input signal, said input signal representing a transmit signal from said first transceiver module (10), a fourth terminal (T4) arranged for receiving a multi carrier power amplifier system output signal, said output signal comprising an amplified representation of the transmit signals from said at least two transceiver modules, and wherein said first and said second terminal (T1, T2) are connected via first single filter means (RX), said second and said third terminal (T2, T3) are connected via second single filter means (TX1), said fourth and said first terminal (T4, T1) are connected via third single filter means (TX2).
Abstract:
Die Erfindung betrifft ein elektrisches Multiband-Bauelement mit mindestens drei Signalpfaden (1, 2, 3) zur Übertragung von Signalen in jeweils einem Frequenzband. Das Bauelement umfasst ferner eine Frequenzweiche (40), an die eingangssei-tig ein Antennenpfad (123) und ausgangsseitig die Signalpfade (1, 2, 3) angeschlossen sind, wobei in mindestens einem der Signalpfade (1, 2, 3) ein Bandpassfilter (32) angeordnet ist, das ein Double Mode SAW Filter umfasst.
Abstract:
The present invention provides a method for using transferred-impedence filtering in RF (radio frequency) receivers (e.g., inside of a mobile communication device), wherein said filtering can be done with MOS-switches transferring impedance of a regular RC or RCL circuit to RF frequency filtering inside an RFIC (radio frequency integrated circuit).
Abstract:
A multiplexer, such as a diplexer, is delineated. The multiplexer may be employed in a communications system that may communicate in multiple frequency bands within a predefined range of frequencies, e.g., 2400 MHz - 4900 MHz. The communications system may operate in a network, such as a wireless local area network, without significant interference from signals used by a cellular/mobile telephone system. The multiplexer may include multiple channels with bandpass filters that may be formed with lumped inductors and lumped capacitors. In at least one of the channels, the bandpass filter may be formed by combining at least one lowpass filter with at least one highpass filter.