Description RF PERFORMANCE TEST CONNECTION DEVICE

Technical Field

[1] The present invention relates to an RF performance test connection device, and more specifically, to an RF performance test connection device in which a test line connection unit for testing the RF performance of communication equipments such as mobile terminals is implemented in the form of PCB pattern, which makes it possible to provide a slim terminal at a low cost. Background Art

[2] Recently, in the mobile communication terminal technology, attempts to manufacture slimmer terminals have been made. That is, studies for reducing the thickness of terminals while a variety of functions are maintained are being continuously conducted. Currently, an RF switch within a mobile terminal has a limit in which the thickness thereof should falls within at least 0.5t.

[3] In orde to test the RF performance of a mobile terminal, an external testing equipment is connected to the mobile terminal so as to perform the RF performance test.

[4] FIG. 1 is a circuit diagram of a conventional RF performance test connection device using a mechanical switch. FIG. 2 is a photograph showing the mechanical switch of FIG. 1.

[5] As shown in FIG. 1, a mobile switch is connected between an antenna in the left side and an RF switch in the right side. The RF performance test is performed by connecting a mobile switch (M/S) cable to the mobile switch of the mobile terminal, the M/S cable being connected to an external testing equipment. Then, since the mobile switch is connected to the RF switch of the mobile terminal, RF signals input and output through the RF switch can be delivered to the external testing equipment (E5515C or the like) so as to test the RF performance.

[6] FIG. 3 is a diagram showing a state where a test line is connected to the mechanical switch.

[7] As shown in FIG. 3, the mechanical mobile switch is connected to the M/S cable so as to come in contact with an RF region and a GND region, respectively. In normal times, the antenna and the RF switch are electrically connected to each other such that RF signals are delivered. However, when the mobile switch is connected to the M/S cable, a contact of the mobile switch is turned off in the direction of the antenna, and is connected to the M/S cable. Further, when the connection of the M/S cable is cut off, the mechanical mobile switch automatically returns so as to maintain the original

connection state.

[8] However, since the mobile switch has a mechanical structure, on/off defects frequently occur. When the mobile switch and the M/S cable are connected to each other, a power loss frequently occurs because of the defective contact.

[9] Further, since power defects caused by an error of calibration value occur, defects frequently occur in the performance test.

[10] Further, since the mobile switch has a mechanical structure, the mobile switch may not return to the original state. Further, it costs a lot to manufacture a single mobile switch.

Disclosure of Invention Technical Problem

[11] An advantage of the present invention is that it provides an RF performance test connection device which can be simply constructed at a low cost such that a mobile terminal can be reduced in thickness. Technical Solution

[12] According to an aspect of the invention, an RF performance test connection device comprises an antenna unit that transmits and receives RF signals; an RF switch unit that switches an internal path of a mobile terminal, through which the RF signals are delivered, depending on the transmission and reception modes of the mobile terminal; a test line connection unit that is connected to the antenna unit and the RF switch unit, respectively, and includes a contact portion implemented of a PCB pattern having a predetermined area of contact surface and a ground portion which is spaced at a predetermined distance from the contact portion along the circumference of the contact portion so as to be grounded and is implemented of a PCB pattern; and a control switch unit that is connected to the antenna unit and the test line connection unit, respectively, and switches the electrical connection between the antenna unit and the test line connection unit in accordance with external control.

[13] Preferably, the ground portion of the test line connection unit has an empty space of which the center is set to the contact portion, and the test line connection unit includes via holes which are formed to connect the contact portion to the antenna unit and the RF switch unit.

[14] Preferably, the test line connection unit has a pin insertion hole formed therearound, to which a test line is fixed.

[15] Preferably, the RF switch unit and the control switch unit are formed as one chip.

Advantageous Effects

[16] According to the present invention, since the test line connection unit implemented of a PCB pattern is provided instead of a mechanical mobile switch, a limit in the

thickness of a mobile terminal is overcome, and it is possible to reduce a manufacturing cost. [17] Further, it is possible to prevent contact defects and signal attenuation from occurring.

Brief Description of the Drawings [18] FIG. 1 is a circuit diagram of a conventional RF performance test connection device using a mechanical switch.

[19] FIG. 2 is a photograph showing the mechanical switch of FIG. 1.

[20] FIG. 3 is a diagram showing a state where a test line is connected to the mechanical switch. [21] FIG. 4 is a block diagram of an RF performance test connection device according to an embodiment of the invention. [22] FIG. 5 is a diagram showing the operation of the circuit and the control switch of the RF performance test connection device shown in FIG. 4. [23] FIG. 6 is a diagram showing a test line connection unit including via holes according to the embodiment of the invention. [24] FIG. 7 is a diagram showing a circuit in which an RF switch unit and a control switch unit are constructed as one chip. [25] FIG. 8 is a diagram showing a state where a test line is connected to the test line connect according to the embodiment of the invention. [26] FIGS. 9 A and 9B are diagrams showing a state where an existing M/S cable is connected to the test line connection unit according to the embodiment of the invention.

Best Mode for Carrying Out the Invention [27] Hereinafter, a preferred embodiment of the present invention will be described with reference to the accompanying drawings. [28] FIG. 4 is a block diagram of an RF performance test connection device according to an embodiment of the invention. [29] As shown in FIG. 4, the RF performance connection device includes an antenna unit 10, a control switch unit 20, a test line connection unit 30, and an RF switch unit

40. [30] Through the antenna unit 10, a communication equipment such as a mobile terminal transmits and receives RF signals to and from outside. [31] The control switch unit 20 serves to switch the connection between the antenna unit

10 and the inside of the mobile terminal. The control switch unit 20 has a terminal through which a separate external control line is connected in such a manner that control can be performed by an external control device such as a computer 50. In

accordance with a control instruction from the connected computer 50, the control switch unit 20 can perform control such that the antenna unit 10 is disconnected from the inside of the mobile terminal during an RF performance test.

[32] Alternatively, an RF control on/off menu 60 may be created in a debugging menu within the mobile terminal such that the control switch unit 20 can be controlled through the RF control on/off menu 60. In this case, the control switch unit 20 does not need to be connected to the computer 50, but can be controlled by the software configured in the mobile terminal.

[33] The test line connection unit 30 is a contact at which a test line for the RF performance test is connected to the mobile terminal, and is connected to the antenna unit 10 and the RF switch unit 40, respectively. The test line connection unit 30 includes a contact portion 31 which is implemented of a PCB pattern having a predetermined area of contact surface and a ground portion 32 which is formed of a PCB pattern so as to be spaced at a predetermined distance from the contact portion 31 along the circumference of the contact portion 31.

[34] The RF switch unit 40 switches an internal path of the mobile terminal through which an RF signal is delivered from the antenna unit 10, depending on the transmission and reception modes of the mobile terminal.

[35] FIG. 5 is a diagram showing the operation of the circuit and the control switch of the RF performance test connection device shown in FIG. 4.

[36] As shown in FIG. 5, the circuit of the antenna unit 10 is connected to the control switch unit 20 through a coil, and the coil of the antenna unit 10 is grounded in parallel through a capacitor.

[37] As shown in FIG. 5, the control switch unit 20 is composed of a field effect transistor (FET) and a resistor. However, the switch circuit of the control switch unit 20 may be constructed by using a Schottky diode or TR as well as the FET. The control switch unit 20 is switched by a control signal input through the external control line.

[38] For example, when an external input voltage applied to the control switch unit 20 is low, the antenna unit 10 is connected to the RF switch unit 40 through the test line connection unit 30 such that an RF signal received by the antenna unit 10 can be input to the mobile terminal or an RF signal generated from the mobile terminal can be transmitted to the outside through the antenna unit 10.

[39] However, when an external input voltage applied to the control switch unit 20 is high, the antenna unit 10 and the test line connection unit 20 is isolated from each other such that an RF signal of the RF switch unit 40 is not delivered to the antenna unit 10. After the antenna unit 10 and the test line connection unit 20 is isolated from each other such that the RF signal is not delivered to the antenna unit 10, the test line

connection unit 30 is connected to the test line so as to perform the RF performance test of the mobile terminal.

[40] The control of the control switch unit 20 can be classified into a test performed by interlocking the mobile terminal, a PC, and a measurer and a test performed by interlocking the mobile terminal and a measurer.

[41] In the test performed by interlocking the mobile terminal, the PC, and the measurer, when a command instruction in a test program is input through RXD and TXD lines of the mobile terminal so as to be delivered to a mobile station modem (MSM), the MSM outputs a control signal so as to perform on/off control.

[42] In the test performed by interlocking the mobile terminal and the measurer, the software is configured in such a manner that the RF control on/off menu 60 is created in the debugging menu included in the menu of the mobile terminal and the on/off control can be performed through the RF control on/off menu 60.

[43] As described above, the contact portion 31 of the test line connection unit 30 is electrically connected to the antenna unit 10 and the RF switch unit 40, and the ground portion 32 of the test line connection unit 30 is grounded.

[44] The contact portion 31 is implemented of a plane PCB pattern having such a sufficient area as to be electrically contacted with the test line which is connected for the RF performance test of the mobile terminal.

[45] The ground portion 32 may be spaced at a predetermined distance from the contact portion 31 so as to be positioned in either side of the contact portion 31 in a state where an electrical line extending from the contact portion 31 is set to a boundary therebetween. In this case, the ground portion 32 may be formed in a semicircle shape of which the internal space is removed, as shown in FIG. 5. Alternatively, as shown in FIG. 6, the ground portion 32 may be constructed of a PCB pattern which completely surrounds the contact portion 31. In this case, the contact portion 31 is electrically connected to the outside through via holes 33.

[46] Meanwhile, the ground portion 32 may include an empty space of which the center is set to the contact portion 31. However, the shape of the ground portion 32 is not limited to such a shape that concentrically surrounds the contact portion 31. The contact portion 32 may have an internal closed surface which isolates the contact portion 31 from outside (refer to FIG. 6), or may be formed in such a shape that the contact portion 31 is simply positioned therein (refer to FIG. 5). Further, the external boundary surface of the ground portion 32 is not limited to a circle, but may be implemented in various shapes such as a rectangle and an indeterminate form. The area of the ground portion 32 is not specifically limited.

[47] The test line connection unit 30 may have a pin insertion hole formed therearound such that the test line connected from outside can be fixed through a pin such as a pogo

pin, of which the upper and lower portions can be moved.

[48] As shown in FIG. 5, the RF switch unit 40 is connected to the test line connection unit 30 through a capacitor, and the capacitor is connected in parallel to a coil so as to be grounded. When several RF signals should be delivered through one path, the RF switch unit 40 switches the path of the RF signals in accordance with a digital input signal, and divides input and output signals by using one antenna. That is, the RF switch unit 40 serves as a duplexer which switches the internal path of the mobile terminal through which signals transmitted and received through the antenna unit 10 are delivered.

[49] FIG. 6 is a diagram of the test line connection unit including the via holes according to the embodiment of the invention.

[50] As shown in FIG. 6, the test line connection unit 30 includes the contact portion 31 having an electrical contact surface and the ground portion 32 which is spaced at a predetermined distance from the contact portion 31 so as to surround the circumference of the contact portion 31. In such a construction, since the contact portion 31 cannot be connected to the outside in a two-dimensional manner, the via holes 33 through which the connection can be three-dimensionally secured are formed on a substrate such that the contact portion 31 can be connected to the antenna unit 10 and the RF switch unit 40, respectively, across the ground portion 32.

[51] FIG. 7 is a diagram showing a circuit in which the RF switch unit and the control switch unit are constructed as one chip.

[52] As shown in FIG. 7, the control switch unit 20 and the RF switch unit 40 can be formed as one chip. When several switches are implemented on a single chip, extra switches may be utilized as the control switch unit 20 such that the control switch unit 20 and the RF switch unit 40 can be constructed as a single chip.

[53] FIG. 8 is a diagram showing a state where the test line is connected to the test line connect according to the embodiment of the invention.

[54] As shown in FIG. 8, when the test line for testing the RF performance of the mobile terminal is connected to the test line connection unit 30, a line projecting from the central portion of the test line comes in contact with the contact portion 31 of the test line connection unit 30. Then, an RF signal from the RF switch unit 40 passes through the contact portion 31 so as to be provided to an RF performance testing equipment through an M/S cable of the test line.

[55] At this time, as the control switch unit 30 is externally controlled before the RF performance test, the connection of the antenna unit 10 is cut off, so that the RF signal is not delivered to the antenna 10.

[56] FIGS. 9A and 9B are diagrams showing a state where an existing M/S cable is connected to the test line connection unit according to the embodiment of the

invention.

[57] As shown in FIGS. 9A and 9B, the RF performance test can be performed by using an existing M/S cable used as the test line. The M/S cable can be connected to the test line connection unit 30 by using only an RF region and a GND region in a state where a portion which automatically returns in accordance with the connection of an existing mechanical switch is removed. Further, in a case of RF using PAD, a configuration shown in FIG. 9A can be implemented.

[58] While the present invention has been described with reference to exemplary embodiments thereof, it will be understood by those skilled in the art that various changes and modifications in form and detail may be made therein without departing from the scope of the present invention as defined by the following claims.