Abstract: An apparatus and method for transmitting and receiving multiple signals inclusively in one channel are provided. The apparatus for transmitting multiple signals inclusively includes a single-sideband signal synthesis unit which synthesizes single-sideband signals having predetermined bands to generate an inclusive single-sideband signal which includes the bands of the single-sideband signals; a main modulation unit which modulates an inclusive single-sideband signal with a primary carrier frequency to generate an inclusive double-sideband signal where the primary carrier frequency is the center frequency; a main band pass filter which allows only any one single-sideband signal of an inclusive double-sideband signal to generate an inclusive single-sideband signal where a primary carrier frequency is an edge frequency of the inclusive band; and an inclusive single-sideband signal transmission unit which transmits an inclusive single-sideband signal.

Abstract: A multiple local oscillation frequency generation apparatus which can generate local oscillation frequencies in at least two frequency bands and a wireless transceiver having the multiple local oscillation frequency generation apparatus are provided. The local oscillation frequency generation apparatus includes: an oscillation unit which comprises a plurality of VCOs that provide at least two local oscillation signals having different frequencies for modulating/demodulating RF signals in at least two frequency bands; a PLL which locks the frequencies of the local oscillation signals provided by the VCOs; a first switch which selects one of the local oscillation signal provided the VCOs according to a frequency band of a RF signal; a frequency conversion unit which converts the frequency of the selected local oscillation signal; and a phase shift unit which generates I-phase and Q-phase local oscillation signals by shifting the phase of a signal output by the frequency conversion unit.

Abstract: 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.

Abstract: A device, system, and method for improving the performance of a tuner for a selected channel by providing a band selection filter controlled by a digital voltage, instead of a notch filter for controlling FM radio signals. The tuner includes a band-selection filter module for selecting a radio frequency RF signal having a frequency within a frequency band of the selected channel using a voltage determined based on digital information; an amplifier module for amplifying the selected RF signal; a mixer module for down-converting the amplified RF signal into a signal having a frequency within an intermediate frequency (IF) band, in which the digital information corresponds to the frequency band of the selected channel.

Abstract: A tuner and a broadcasting signal receiver including the tuner. The tuner includes a band selection module that selects an RF broadcasting signal within the frequency band corresponding to a selected channel, and a low noise amplifier module that amplifies the signal with a specific received signal strength indicator (RSSI) to produce an RF broadcasting signal with a specific gain.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: An apparatus and method for transmitting and receiving multiple signals inclusively in one channel are provided. The apparatus for transmitting multiple signals inclusively includes a single-sideband signal synthesis unit which synthesizes single-sideband signals having predetermined bands to generate an inclusive single-sideband signal which includes the bands of the single-sideband signals; a main modulation unit which modulates an inclusive single-sideband signal with a primary carrier frequency to generate an inclusive double-sideband signal where the primary carrier frequency is the center frequency; a main band pass filter which allows only any one single-sideband signal of an inclusive double-sideband signal to generate an inclusive single-sideband signal where a primary carrier frequency is an edge frequency of the inclusive band; and an inclusive single-sideband signal transmission unit which transmits an inclusive single-sideband signal.

Abstract: 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.