The present invention relates to a method of installing an antenna of a wireless module, and a coaxial connector to be used in the method of installing the antenna.
When a wireless module equipped with a built-in antenna is installed at one position inside a casing of a device in which the wireless module is to be installed, there is no problem if the built-in antenna can exhibit desired antenna properties at the one position. In this case, it is not necessary to provide an external antenna with a relatively high manufacturing cost and a large number of design processes. Accordingly, the manufacturing cost can be less expensive and the design processes are less.
On the other hand, when it is difficult to use the wireless module equipped with the built-in antenna, or even when the wireless module equipped with the built-in antenna is installed at one position inside a casing, but the built-in antenna cannot exhibit desired antenna properties, or when it is difficult to install the wireless module at such one position, it is necessary to install the wireless module using an external antenna disposed inside the casing.
If it is clear whether the wireless module equipped with the built-in antenna can be used or the wireless module that uses the external antenna should be used in advance, there is no problem. However, if it is not clear which wireless module should be used, it is necessary to install the wireless module using the external antenna.
After the wireless module using the external antenna is installed, if it is found to be possible to use the wireless module equipped with the built-in antenna, the external antenna, which is expensive and requires more design man-hours, will be unnecessarily used, thereby increasing the cost and lowering work efficiency. Patent Reference 1 has disclosed such conventional techniques.    Patent Reference 1: Japanese Patent Publication No. 2003-123915
A conventional coaxial connector is used in a pair with a conventional coaxial change-over switch. The conventional coaxial change-over switch has been widely used in portable communication devices such as a mobile phone for inspecting high-frequency circuits. FIG. 13 is a view showing a conventional coaxial change-over switch 121. The coaxial change-over switch 121 is similar to one disclosed in Patent Reference 2.    Patent Reference 2: Japanese Patent Publication No. 2001-176612
The coaxial change-over switch 121 includes a stationary terminal 124 and a movable terminal 125, which are disposed in an insulated housing 122 and can contact with and separate from each other. A center conductor 129 is supported on an insulated housing 127 of the coaxial connector 126. When the center conductor 129 is moved downward through an insertion hole 135 formed in the insulated housing 122, the stationary terminal 124 stays stationary, and only the movable terminal 125 moves to a position indicated with a hidden line, so that the stationary terminal 124 is disconnected from the movable terminal 125.
When the movable terminal 125 is disconnected from the stationary terminal 124, the center conductor 129 of the coaxial connector 126 is in a state of contacting only with the movable terminal 125. As a result, it is possible to switch a signal circuit between the movable terminal 125 and the stationary terminal 124 to another signal circuit between the movable terminal 125 and the center conductor 129. Here, the change-over operation like this has been used to inspect high-frequency performance of a device equipped with a high-frequency circuit such as a mobile phone.
Conventionally, the coaxial change-over switch 121 has been used solely for inspection and only useful for inspection. More specifically, the coaxial change-over switch 121 has been used only upon inspection of a device after production and usually used only once, and therefore it has not been effectively used. In addition, an outer conductor 128 of the coaxial connector 126 is simply designed so as to be able to engage the lower end section 133 with an annular groove 132 of the coaxial change-over switch 121. Further, the coaxial connector 126 extends in the fitting direction. Therefore, the coaxial connector 126 is not structurally suitable to constantly connect between the coaxial connector 126 and the coaxial change-over switch 121.
In order to solve the above-described problems in the conventional techniques, an object of the present invention is to provide a method of installing an antenna. In the present invention, even when it is not clear whether a wireless module with a built-in antenna should be used or a wireless module using an external antenna should be used, it is possible to select one of the built-in antenna and the external antenna to a situation, and to freely switch between the built-in antenna and the external antenna. In addition, another object of the present invention is to provide a coaxial connector to be used in the method installing the antenna.
A further object of the present invention is to provide a coaxial connector capable of constantly connecting with a coaxial change-over switch, so that the coaxial change-over switch can be effectively used.
Further objects and advantages of the invention will be apparent from the following description of the invention.