The present disclosure relates to the field of communications, and particularly to a rotary USB (Universal Serial BUS) interface device in a terminal device.
During designing of a rotary USB interface data card, one of the essential factors for determining of low frequency indices of OTA (Over The Air) is to ensure good performance of the rotary USB interface. The connection ability of a wireless device to a network and the effect of a wireless device user on radiation and reception performance can be verified by an OTA test, and the OTA indices contain TRP (Total Radiated Power) and TIS (Total Isotropic Sensitivity). TRP evaluates radiation performance of the wireless device, and a greater TRP value indicates a better radiation performance of the wireless device. TIS evaluates reception performance of the wireless device, and a smaller TIS value indicates a better reception performance of the wireless device.
Generally speaking, the width of the ground wire 20 of the USB 10 and the width of the ground wire 50 in the FPC or cable are controlled by the size of the overall structure of the data card, and the rotary shaft 30, the spring tab or presser tab 40 and the copper covering grounding region 60 are connected with each other in generally a point contact manner, which lower the grounding performance of the data card. When OTA test is performed on the rotary USB interface data card in the relevant art, it is found that its TRP/TIS indices are relatively poor in the case of 800 MHz and 900 MHz. It can be seen that the grounding performance of the rotary USB interface data card directly affects the OTA low frequency indices of the antenna 80.
To enhance the grounding performance of the rotary USB interface data card, the structure of the rotary USB interface data card may be improved.
From the structure of the data card shown in
The improved rotary USB interface data card shown in
An embodiment of the present disclosure provides a rotary USB interface device, which solves the problems that the structure of the rotary USB interface device in the relevant art is complicated, and the transmitting/receiving performance is unsatisfactory due to the poor OTA indices.
A rotary USB interface device includes:
an USB module, rotating relative to a PCB by means of a rotary shaft,
wherein the USB module contains a first ground wire, wherein the first ground wire is connected to the rotary shaft and the rotary shaft is connected to a conductive layer, so as to form a first grounding path of the USB module,
wherein an insulation layer is provided between a grounding layer on the PCB and the conductive layer, separating the first grounding path from a second grounding path formed by the grounding layer of the PCB.
In the above device, the thickness of the insulation layer, the value of the area of the conductive layer and the value of the area of the grounding layer may be set in accordance with an open circuit voltage which is formed when the first grounding path is separated from the second grounding path of the PCB.
In the above device, the insulation layer may be of an insulation material.
In the above device, the insulation layer may be the PCB.
In the above device, the conductive layer may be of a metal material or a conductible material.
In the above device, the metal material may be selected from any one of or any combination of the following materials: stainless steel and copper.
In the above device, the conductible material may include conductive cloth.
The advantageous effects of the present disclosure are:
in the rotary USB interface device provided in the embodiments of the present disclosure, the first grounding path of the USB module is separated from the second grounding path of the PCB by virtue of the insulation layer. Thus an open circuit voltage is formed, the voltage difference between the grounding path of the USB module and the grounding path of the PCB is maintained stable, the overall device obtains a stable grounding signal, the grounding performance is enhanced and the transmitting/receiving performance of the device is improved. The simple structure of the device overcomes defects of the complicated structure, the cumbersome production process and the expensive costs of the device in the relevant art. The device according to embodiments of the present disclosure is a simpler implementation solution with lower costs, greater producibility and easier operation, in comparison with the conventional means such as spraying conductive paint and adhering conductive foam.
In order to make the technical problem to be solved by the present disclosure, the technical solutions and the advantageous effects more clear and apparent, the present disclosure is explained in further detail below in connection with the accompany drawings and embodiments. It should be understood that, the embodiments described herein are only used for explaining the present disclosure, rather for limiting the present disclosure.
For the problems that the poor grounding performance of the rotary USB interface device in the relevant art results in poor OTA indices and poor transmitting/receiving performance of the device, the embodiments of the present disclosure provide a rotary USB interface device structure, which separates a first grounding path of an USB module of the device from a second grounding path of a PCB, to form an open circuit to maintain a stable voltage difference. The principle of structure of the rotary USB interface device is shown in
As shown in
By means of the insulation layer 150, the grounding layer 160 of the PCB and the conductive layer 140 are separated from each other, and an open circuit configuration is formed between the conductive layer 140 and the grounding layer 160. A stable voltage difference is maintained between the PCB and the USB module due to the open circuit configuration, so that low-frequency indices are improved and a desirable transmitting/receiving performance is obtained. The insulation layer 150 may be a PCB or other insulation materials.
The structure of a rotary USB interface device provided in the first embodiment of the present disclosure is shown in
In said rotary USB interface device, the USB module 110 is able to rotate relative to the PCB by means of the rotary shaft 130. The first ground wire 120 included in the USB module 110 is connected to the rotary shaft 130, and the rotary shaft 130 is connected to the conductive layer 140, such that a path is embodied in the conductive layer 140, the rotary shaft 130 and the USB module 110, and the first grounding path of the USB module 110 is formed, The insulation layer 150 is provided between the grounding layer (namely exposed copper covering grounding region) 160 on the PCB 170 and the conductive layer 140, separating the first grounding path from the second grounding path of the PCB 170. The grounding layer 160 on the PCB 170 forms the second grounding path on the PCB.
The thickness of said insulation layer 150, the value of the area of the conductive layer 140 and the value of the area of the grounding layer 160 are set in accordance with the open circuit voltage which is formed when the provided first grounding path is separated from the second grounding path of the PCB 170.
Said conductive layer may be of a metal material or a conductible material. The metal material may be selected from any one of or any combination of the following materials: stainless steel and copper, and the like. The conductible material may be selected from conductive cloth, and the like.
The structure of the rotary USB interface device provided in the second embodiment of the present disclosure is shown in
In this embodiment, the USB module 110, the first ground wire 120 in the USB module 110, the rotary shaft 130 and the conductive layer 140 are provided on a side of the PCB 170 opposite to the grounding layer 160, so as to achieve a purpose that the PCB 170 serves as an insulation layer. By means of the PCB 170, the first grounding path of the USB module 110 formed by the conductive layer 140, the rotary shaft 130 and the first ground wire 120 in the USB module 110 is separated from a second grounding path formed by the grounding layer 160 on the PCB 170.
The rotary USB interface devices provided in said first and second embodiments establish an open circuit configuration between the grounding paths of the USB module 110 and the PCB 170 of the rotary USB interface device, so as to disconnect the first grounding path of the USB module 110 from the second grounding path of the PCB 170, such that an outer conductor of the USB module 110 has a voltage effect in an open circuit space state by means of the conductive layer 140 and the grounding layer 160 of the PCB 170, thus an open circuit voltage A is formed. If the value of the area of the conductive layer 140, the thickness of the insulation layer 150 and the value of the area of the grounding layer 160 of the PCB 170 are determined, the open circuit voltage A would maintain constant. In this way, a voltage uncertainty introduced by the rotary shaft 130 would be negligible as the presence of the voltage A, and therefore it is possible to decide that A becomes the main voltage difference of the overall data card structure. Accordingly, it is possible to determine the voltage difference between the first ground wire 120 of the USB module 110 and the grounding layer 160 of an outer metal wall and the PCB 170 by means of the open circuit voltage A, such that the grounding signal obtained by the overall data card structure tends to be stable. The reason why the OTA low-frequency indices, especially the TIS indices, of the rotary USB interface device in the relevant art is relatively poor is that point contact structure accumulation of a plurality of contact points causes instability and uncertainty of the grounding signal. In contrast, according to the embodiments of the present disclosure, an open circuit voltage A introduced by the open circuit configuration can maintain the stability of the grounding signal of the rotary USB interface device, thus improving the OTA low-frequency indices, especially the TIS indices.
The rotary USB interface devices provided in the embodiments of the present disclosure may be used in a terminal device or a wireless device of, such as, TD-SCDMA (Time Division-Synchronous Code Division Multiple Access) type, WCDMA (Wide-band Code Division Multiple Access) type, EVDO (Evolution Data Only) type. The purpose of maintaining the grounding signal stable is achieved by separating the first grounding path of the USB module from the second grounding path of the PCB. The simple structure of the device overcomes defects of the complicated structure, the cumbersome production process and the expensive costs of the device in the relevant art. The device according to embodiments of the present disclosure is a simpler implementation solution with lower costs, greater producibility and easier operation, in comparison with the conventional means such as spraying conductive paint and adhering conductive foam. At the same time, by means of the simple open circuit configuration, the TIS low-frequency indices of the rotary USB interface device is improved, the TRP performance of the device is ensured, and thus the desirable transmitting/receiving performance of the device is ensured.
The following table 1 shows TIS data of a rotary USB interface device obtained through tests, respectively, when employing the open circuit configuration provided in the embodiments of the present disclosure and employing the conventional configuration given in the relevant art.
62 and 124 in table 1 are channel values, and dBm is the measurement unit of the TIS.
The following table 2 shows TIS data of another rotary USB interface device obtained through tests, respectively, when employing the open circuit configuration provided in the embodiments of the present disclosure and employing the conventional configuration given in the relevant art.
1, 62 and 124 in table 2 are channel values, and dBm is the measurement unit of the TIS.
It can be seen from the TIS data obtained through tests in the above Table 1 and Table 2 that, the TIS of the rotary USB interface device employing the open circuit configuration provided in the embodiments of the present disclosure is improved to a greater extent, thus the rotary USB interface device employing the open circuit configuration has a better transmitting/receiving performance than the conventional rotary USB interface device.
The above description illustrates and describes a preferable embodiment of the present disclosure, but as mentioned above, it should be understood that the present disclosure is not limited to thereto. What described and illustrated herein should not be considered as an exclusion of other embodiments, yet can be used for any other combinations, modifications and environments, and can be changed within the conception scope of the disclosure described herein by the above teaching or technology or knowledge in relevant arts. The alternations and modifications made by the person skilled in the art which do not depart from the scope of the disclosure should fall into the scope of protection defined by the appended claims of the disclosure.
Number | Date | Country | Kind |
---|---|---|---|
201110043533.4 | Feb 2011 | CN | national |
Filing Document | Filing Date | Country | Kind | 371c Date |
---|---|---|---|---|
PCT/CN2011/077733 | 7/28/2011 | WO | 00 | 9/16/2013 |