Abstract: A method for tuning a resonant frequency of an antenna includes the steps of providing an antenna having a radiating element operating at a present resonant frequency, determining a target operating frequency of the antenna, mensurating the present resonant frequency of the antenna and calculating a frequency offset between the present resonant frequency and the target operating frequency, providing a dielectric film covered on the radiating element, tuning an thickness and an area of the dielectric film, and repeating the mensurating step and the tuning step till the frequency offset reaches zero.

Abstract: A dual-band antenna (1) includes a first antenna (2) and a second antenna (3). The first antenna includes a u-shaped first dipole half (11) and an n-shaped second dipole half (12). The first dipole half is disposed above the second dipole half with a space therebetween and the two dipole halves are mirror imaged. The second antenna includes a u-shaped third dipole half (21) and an n-shaped fourth dipole half (22). The first and the third dipole halves are crossly connected with each other at bottom. The second and the fourth dipole halves are crossly connected with each other at top.

Abstract: A dual-band antenna (1) includes a first antenna (2) and a second antenna (3). The first antenna includes a first dipole half (11) and a second dipole half (12). The first dipole half is disposed above the second dipole half with a space therebetween and the two dipole halves are corresponding to each other in a lengthwise direction. The second antenna includes a coaxial cable (4) including an inner conductor feeding the first antenna and comprising an exposed extending section (40) acting as a radiating portion of the second antenna, and a ground patch (5) electrically connected with the second dipole half.

Abstract: An electrical connector (1) used in high frequency signal transmission filed includes an insulative housing (2), an immovable contact (5) retained in the housing. The immovable contact includes a main body (50), a cantilevered arm (51) longitudinally extending from the main body, a soldering portion (53) backwardly extending from the main body. The cantilevered arm forms an angle to the main body. The main body is a substantially “Z” shape to prolong the current path of the immovable contact and to cut the area of the immovable contact, thereby decreasing the capacity of the immovable contact.

Abstract: A printed PIFA antenna (1) for an electronic device includes a multi-layer substrate, a U-shaped radiating element or rectangular-wave shaped radiating element disposed in the substrate, a ground portion disposed on surfaces of the substrate and a feeder cable including an inner conductor connecting with radiating element and an outer conductor connecting with ground portion. A multi-layer printed technology is introduced into a design of a PIFA antenna, which will achieve a very compact antenna structure.