Abstract: A wearable antenna comprises: an upper substrate made of a solid material; an inner open ring radiator formed on an upper surface of the upper substrate and having a first slit formed therein; an outer open ring radiator formed in a ring shape having the same center as the inner open ring radiator and having a larger radius on the upper surface, and having a second slit formed therein to open a partial area; a feeding portion formed on a lower surface of the upper substrate and transmitting a feed signal applied from an input port to each of the two open ring radiators through two vias penetrating the upper substrate; a lower substrate spaced apart from the lower surface of the upper substrate by a predetermined distance and made of a flexible material; and a ground plane formed on a lower surface of the lower substrate.

Abstract: Disclosed is an optical communication receiver capable of compensating a DC offset while preventing an input load effect. The optical communication receiver includes an optical signal detector; an amplifier inputted with a photocurrent outputted from the optical signal detector; and a DC offset compensation unit provided therein with a third transistor and a fifth transistor which are connected in series to each other to prevent an input load effect, wherein the DC offset compensation unit compensates a DC offset by outputting at least a portion of DC current inputted to the amplifier to ground through the third transistor and the fifth transistor when the photocurrent is an over current more than a predetermined set value.

Abstract: Disclosed is an optical communication receiver capable of compensating a DC offset while preventing an input load effect. The optical communication receiver includes an optical signal detector; an amplifier inputted with a photocurrent outputted from the optical signal detector; and a DC offset compensation unit provided therein with a third transistor and a fifth transistor which are connected in series to each other to prevent an input load effect, wherein the DC offset compensation unit compensates a DC offset by outputting at least a portion of DC current inputted to the amplifier to ground through the third transistor and the fifth transistor when the photocurrent is an over current more than a predetermined set value.

Abstract: There are provided a modeling circuit of a high-frequency device capable of providing a more accurate modeling circuit having a higher-order resonance by dividedly modeling an overlap zone and a non-overlap zone of the high-frequency device, and a modeling method thereof.

Abstract: Provided is a frequency conversion mixer. The frequency conversion mixer includes a transconductance stage, a switching stage, a load stage, a current bleeding circuit, and a bias stage. The transconductance stage receives an RF signal, and outputs a current corresponding to a voltage of the RF signal. The switching stage switches the current which is outputted from the transconductance stage in response to a local oscillation signal, for frequency conversion the RF signal into an intermediate frequency (IF) signal. The load stage is connected between the switching stage and a supply voltage terminal. The current bleeding circuit is connected parallel with the switching stage, especially, embodying inverter structure with transconductance stage to get not only current bleeding effect but also current reuse effect, and one resonant inductor for reducing noise which is generated in parasitic capacitance at node between transconductance stage and switching stage.

Abstract: Provided is a frequency conversion mixer. The frequency conversion mixer includes a transconductance stage, a switching stage, a load stage, a current bleeding circuit, and a bias stage. The transconductance stage receives an RF signal, and outputs a current corresponding to a voltage of the RF signal. The switching stage switches the current which is outputted from the transconductance stage in response to a local oscillation signal, for frequency conversion the RF signal into an intermediate frequency (IF) signal. The load stage is connected between the switching stage and a supply voltage terminal. The current bleeding circuit is connected parallel with the switching stage, especially, embodying inverter structure with transconductance stage to get not only current bleeding effect but also current reuse effect, and one resonant inductor for reducing noise which is generated in parasitic capacitance at node between transconductance stage and switching stage.

Abstract: Provided is a Low Noise Amplifier (LNA). Embodiments of the present invention provide LNAs including: a common gate amplifier circuit configure to amplify a signal of an input node to which an Alternating Current (AC) component is provided and transfer the amplified signal to an amplifier node; and a negative-feedback amplifier circuit configured to amplify a signal of the amplifier node, transfer the amplified signal to an output node, wherein the negative-feedback amplifier circuit includes a feedback capacitor and a feedback inductor connected in series between the amplifier node and the output node to form a negative feedback. the LNA of the present invention forms a negative feedback exclusive of a feedback resistance, such that a broad frequency bandwidth is obtained and noise and heat are reduced.

Abstract: There are provided a modeling circuit of a high-frequency device capable of providing a more accurate modeling circuit having a higher-order resonance by dividedly modeling an overlap zone and a non-overlap zone of the high-frequency device, and a modeling method thereof.

Abstract: An apparatus for introducing electromagnetic perturbation into a target device includes a piezoelectric transducer configured to deflect in response to an applied voltage and a perturber configured to deflect in response to deflection of the piezoelectric transducer. The deflection of the perturber causes electromagnetic perturbation, and in some cases a phase shift, in the target device. The electromagnetic perturbation may also be used to tune microwave devices such as filters, resonators, and oscillators.