Abstract: An impedance matching circuit, a semiconductor element and a radio communication device using the same, adjusting bandwidth while permitting it to be constructed on the semiconductor element by reducing its occupation area. Since a reactance compensating distributed constant line (31) compensates reactance (BL, XS) of a load (6) and a quarter-wave transmission line (32) and an impedance inverting distributed constant line (33) composing an impedance inverting circuit (K inverter or J inverter) corresponding to the degree of impedance (ZL, ZS) of the load (6) match the impedance (ZL, ZS) of the compensated load (6) and output the input signals (SI1, SI2) at the preset bandwidth, adjustment of bandwidth can be made while miniaturizing the impedance matching circuit (7a) by shortening the line length of the reactance compensating distributed constant line (31) and the quarter-wave transmission line (32).

Abstract: An impedance matching circuit and a semiconductor element and a radio communication device using the same which is capable of adjusting bandwidth while permitting it to be constructed on the semiconductor element by reducing its occupation area. Since a reactance compensating distributed constant line (31) compensates reactance (BL, XS) of a load (6) and a quarter-wave transmission line (32) and an impedance inverting distributed constant line (33) composing an impedance inverting circuit (K inverter or J inverter) corresponding to the degree of impedance (ZL, ZS) of the load (6) match the impedance (ZL, ZS) of the compensated load (6) and output the input signals (SI1, SI2) at the preset bandwidth, adjustment of bandwidth can be made while miniaturizing the impedance matching circuit (7a) by shortening the line length of the reactance compensating distributed constant line (31) and the quarter-wave transmission line (32).

Abstract: Disclosed are a method of measuring ESR in a sample located outside a resonator using the B1 leaking to the exterior from the end of the resonator; and an ESR device comprised of at least a resonator capable of applying a B1 leaking from the end of the resonator to a sample located outside the resonator, and a magnet located on the resonator side of a plane containing the end of the resonator that is capable of applying a B0 and a modulation field. These inventions enable ESR measurement of the interior of large samples.

Abstract: Disclosed are a method of measuring ESR in a sample located outside a resonator using the B1 leaking to the exterior from the end of the resonator; and an ESR device comprised of at least a resonator capable of applying a B1 leaking from the end of the resonator to a sample located outside the resonator, and a magnet located on the resonator side of a plane containing the end of the resonator that is capable of applying a B0 and a modulation field. These inventions enable ESR measurement of the interior of large samples.