Nec Corporation

Ryoh Itoh

Yukio Yokoyama

Takao Ono

Jun Uchida

The present invention enables to restrain the enlargement of the wireless communication apparatus and prevent the manufacturing processes from increasing and to increase the frequency bands which can be used by the wireless communication. An antennaincludes a first ground pattern, a second ground pattern, a hinge conductor memberand a current control circuit. The first ground patternis formed on a first printed wiring board. The hinge conductor memberis arranged on a hinge Z which connects indirectly the first printed wiring boardand a second printed wiring boardeach other. The current control circuitis arranged on the first printed wiring board. The current control circuithas a function to flow the electric current of a first frequency band and attenuate the electric current of a second frequency band. An electric current of the first frequency band flows from a feeding sourceto the second ground patternand flows into the first ground patternthrough the hinge conductor memberand the current control circuit. A part, on which the electric current of the first frequency band flows, functions as an antenna which communicate the signal of the first frequency band. An electric current of the second frequency band flows from the feeding sourceto the second ground patternand flows until reaching the current control circuitthrough the hinge conductor member. A part, on which the electric current of the second frequency band flows, functions as an antenna which communicate the signal of the second frequency band.

Antenna, wireless communication apparatus and method of configuring antenna

A portable wireless unit of the invention has a first plane antenna smaller than an antenna size determined by a desired frequency, and a second plane antenna presenting an antenna size determined by the desired frequency on the whole by coupling with the first plane antenna.

Portable wireless unit

In a portable radio of the present invention, in order to reduce an influence of a flexed unit near an antenna with a structure that the antenna is fitted to a flexion portion of the unit, a conduction portion of the unit is divided into upper and lower sections interposing an antenna fitting portion. An actual resistor is inserted into the middle of an connection line (cable) for electrically connecting the upper and lower sections, thereby cutting a high frequency current. Alternatively, an inductor is inserted into the middle of the connection line (cable), thereby cutting a conduction between the upper and lower sections in a high frequency manner. The unit of the portable unit may be a structure that it is divided into upper and lower unit sections and it is foldable.

Portable radio

A portable radio apparatus includes an antenna, a transmission/reception circuit, a first matching circuit, a second matching circuit, and a first switch. The antenna consists of a linear element portion constituting a whip antenna and a helical coil portion constituting a helical antenna fixed to a distal end of the linear element portion through an insulating portion. The antenna is supported to be extendible from a housing. The transmission/reception circuit is connected to the helical coil portion in an antenna accommodation state and connected to the linear element portion in an antenna extension state. The first matching circuit performs impedance matching between the helical coil portion and the transmission/reception circuit. The second matching circuit performs impedance matching between the linear element portion and the transmission/reception circuit. The first switch connects the helical coil portion to the first matching circuit in the antenna accommodation state and connects the linear element portion to the second matching circuit in the antenna extension state.

Portable radio apparatus

In order to achieve two-way communications at two different frequencies, an impedance matching circuit is coupled to an antenna. The circuit includes a first inductor which is directly coupled to the antenna. The first inductor induces antenna input impedance to be capacitive at a first resonant frequency and induces the antenna input impedance to be inductive at a second resonant frequency. The first resonant frequency is lower than the second resonant frequency. Further, a first capacitor is coupled to the first inductor. By providing the first capacitor, a reactance component at the first resonant frequency is rendered substantially equal to a reactance component at the second resonant frequency. Further, the circuit includes a second inductor and a second capacitor which are coupled between the second means and a feeder. The combination of the second inductor and the second capacitor is provided to adjust impedance, defined by the antenna and the first inductor and the first capacitor, to characteristic impedance of the feeder at the first and second resonant frequencies.

Two-frequency impedance matching circuit for an antenna

A miniature and high performance antenna applicable to a radio communication apparatus and made up of a straight antenna rod and an antenna coil or coil element. A first whip antenna has a first portion retractable into the casing of the apparatus and a second portion constantly positioned externally of the casing. A second whip antenna has a coil element in the form of a loading coil having a predetermined number of turns. The second whip antenna is coaxially provided on the upper end of the first whip antenna and slidable relative to and in the axial direction of the first whip antenna. The second portion of the first whip antenna is movable between a position where one end of the coil element is disengaged from one end of the second portion and a position where the former is engaged with the latter. The antenna exhibits a desirable electric characteristic when pulled out of the casing of the apparatus and, in addition, promotes the efficient use of the limited space available in the casing.

Growing community of inventors

Tokyo, Japan

Ryoh Itoh