摘要:
Disclosed is a variable gain amplifier. The variable gain amplifier includes a gain control unit to transmit input differential signals as they are when it operates in a high gain mode, and to transmit the signals by way of predetermined impedances when operating in a low gain mode, and an amplification unit to amplify the input differential signals output from the gain control unit.
摘要:
A variable gain amplifier (VGA) having stable input impedance matching and a stable noise figure in spite of a variation of an amplification gain is provided. In an embodiment of the VGA, a first stage of a cascode amplification unit has a fixed impedance regardless of a change of an amplification gain, and a variable gain determination unit comprised of a plurality of transistors is formed at an upper stage in the cascode amplification unit. Accordingly, a change of an input impedance of the cascode amplification unit due to the change of the amplification gain is minimized. In another embodiment of the VGA, an amplification gain of an amplification unit is controlled by adjusting a voltage applied to the amplification unit by controlling a current to be output by a current supply source, and stable input impedance matching and a stable noise figure are obtained.
摘要:
A wide band antenna, which has a wide frequency band so that it can be used in a wireless local area network (WLAN) and can be manufactured in a small size at a low cost, is provided. The wide band antenna includes a first antenna unit, a supply cable, a first connector coupler, a second antenna unit, a balun, a stub, and a second connector coupler. A frequency band increases when coupling occurs between the stub and the first antenna unit or the second antenna unit.
摘要:
A silicon tuner using a sigma delta-analog digital converter (SD-ADC) includes a radio frequency (RF) signal processor to process an RF signal input from an antenna, a mixer to convert the RF signal into an intermediate frequency (IF) signal, an SD-ADC to convert an IF signal into a digital signal, and an IF signal processor to process the converted IF signal. Accordingly, a silicon tuner in which a signal processor and a size are improved is provided.
摘要:
A variable gain amplifier (VGA) having stable input impedance matching and a stable noise figure in spite of a variation of an amplification gain is provided. In an embodiment of the VGA, a first stage of a cascode amplification unit has a fixed impedance regardless of a change of an amplification gain, and a variable gain determination unit comprised of a plurality of transistors is formed at an upper stage in the cascode amplification unit. Accordingly, a change of an input impedance of the cascode amplification unit due to the change of the amplification gain is minimized. In another embodiment of the VGA, an amplification gain of an amplification unit is controlled by adjusting a voltage applied to the amplification unit by controlling a current to be output by a current supply source, and stable input impedance matching and a stable noise figure are obtained.
摘要:
An amplifier that achieves impedance matching in a wide frequency band is provided. The wide-band amplifier includes a first n-type metal oxide semiconductor (NMOS) transistor which receives an input signal; a second NMOS transistor which buffers a signal amplified by the first NMOS transistor; a third NMOS transistor which amplifies a signal supplied from a source of the first NMOS transistor; and an output terminal which outputs a signal obtained by combining the signal buffered by the second NMOS transistor with the signal amplified by the third NMOS transistor.
摘要:
A broadband low noise amplifier and amplification method is provided. The broadband low noise amplifier includes an input terminal into which a radio frequency (RF) signal received by an antenna is input, an output terminal from which an amplified RF signal is output, at least one gain control part connected in parallel with loads of the output terminal to adjust the gain of the amplified RF signal, and at least one load tuning part that resonates with loads of the output terminal to adjust the resonance frequency of the load impedance. The method includes amplifying the input RF signal and outputting the amplified RF signal to an output terminal, where a gain of the amplified RF signal is adjusted by switching operations of at least one switching device connected in parallel with a load of the output terminal.
摘要:
A transceiver device capable of calibration, and a calibration method used by the transceiver device. The transceiver device includes a reference transceiver, a plurality of remaining transceivers, and a plurality of transmission calibration paths connecting the remaining transceivers to the reference transceiver for transmission calibration of the remaining transceivers. An envelope detector included in the reference transceiver is shared with the remaining transceivers. When implementing a multiple input multiple output (MIMO) transceiver in a single chip, the chip size and manufacturing cost of the MIMO transceiver device can be substantially reduced.
摘要:
A method and apparatus for controlling a multi-input multi-output (MIMO) radio frequency (RF) transceiver having a plurality of RF blocks using a single serial programming interface (SPI) are provided. The MIMO system includes: a MIMO transceiver, having one or more input and output units and a serial interface conversion unit controlling the input and output units; and a controller, which controls the MIMO transceiver. The serial interface conversion unit receives control data from the controller via a serial programming interface (SPI), decodes the received control data to have a format appropriate for controlling the input and output units, and encodes data received from the input and output units to be compatible with the SPI. Accordingly, it is possible to realize a small-sized MIMO system having a simple structure and to reduce the probability of errors occurring in the process of controlling a plurality of RF blocks of the MIMO system.