Patent Application
20080150816
This invention generally relates to wireless communications and more specifically to antenna feed arrangement in mobile terminals, e.g., slide-type terminals.
Antennas are critical elements in mobile products and their number is increasing with required wireless access systems in one wireless product using a small space. Current mobile terminals have to support multiple cellular radio systems, such as GSM (global system for mobile communications), WCDMA (wideband code division multiple access), CDMA (wideband code division multiple access), CDMA2000, etc., and non-cellular radio systems, such as WLAN (wireless local area network), BLUETOOTH, GPS (global positioning system), DVB-H (digital video broadcasting—handheld), etc. The design of antennas for all these frequency bands is a challenging task because there is a limited amount of space available for the antennas.
According to a first aspect of the invention, an apparatus, comprises: a first part comprising a radiating element; a second part comprising a further radiating element, wherein the first and second parts are configured to move relative to each other during operation; and at least one connecting flex, for providing a flexible connection between the first and second parts, for providing a radio frequency signal between the radiating element and the further radiating element during the operation.
According further to the first aspect of the invention, the first and second parts may be configured to slide relative to each other during the operation.
Still further according to the first aspect of the invention, the radiating element and the further radiating element may be printed wiring boards or flexible wiring boards.
According further to the first aspect of the invention, the apparatus may comprise at least one more connecting flex for providing a direct current power between the second and first parts.
According still further to the first aspect of the invention, the first part or the second part may be combined with the at least one connecting flex as one part and the one part may be made from a plastic flexible material.
According still further to the first aspect of the invention, the at least one connecting flex may be made of a plastic flexible material and may comprise at least one flexible electrically conducting strip. Further, the radio frequency signal may be provided to the radiating element or to the further radiating element through the at least one flexible electrically conducting strip, wherein a feed arrangement for the radio frequency signal may be provided to the at least one flexible electrically conducting strip using a feed pad on the first or second part. Further still, the radio frequency signal may be provided to the radiating element or to the further radiating element through the at least one flexible electrically conducting strip using a direct electrical connection between the at least one flexible electrically conducting strip and a printed wiring board of the first part or a further printed wiring board of the second part, respectively, but without connecting the at least one flexible electrically conducting strip to an RF ground of the printed wiring board or the further printed wiring board, respectively. Still further, the at least one flexible electrically conducting strip may be made of copper.
According yet further still to the first aspect of the invention, the at least one connecting flex or at least one further connecting flex may be configured for providing between the second and first parts at least one of: a) a connection for a direct current power, b) a connection for grounding or short circuiting, and c) a connection for a further electrical signal. Further, the connection for the grounding or short circuiting may comprise discrete components.
Yet still further according to the first aspect of the invention, the radio frequency signal may be provided to the radiating element or to the further radiating element through at least one flexible electrically conducting strip of the at least one connecting flex, wherein a feed arrangement for the radio frequency signal to the at least one flexible electrically conducting strip may be provided on the first or second part using one of: a) galvanic feeding, b) capacitive feeding, and c) inductive feeding. Further, the feed arrangement may comprise a matching circuit. Still further, the feed arrangement may comprise a balun.
Still yet further according to the first aspect of the invention, the apparatus may be for wireless communications in cellular or non-cellular systems.
Still further still according to the first aspect of the invention, the apparatus may be part of or implemented as a mobile terminal, a portable communication device, a wireless device, a mobile communication device, a mobile phone or a mobile device for wireless communications in cellular or non-cellular systems.
According to a second aspect of the invention, a method, comprises: providing a flexible connection between a first part and a second part of an electronic device, wherein the first part comprises a radiating element and the second part comprises a further radiating element, and the first part and the second part are configured to move relative to each other during operation of the electronic device; and providing a radio frequency signal between the radiating element and the further radiating element during the operation.
According further to the second aspect of the invention, the first and second parts may be configured to slide relative to each other during the operation.
Further according to the second aspect of the invention, the radiating element and the further radiating element may be printed wiring boards or flexible wiring boards.
Still further according to the second aspect of the invention, the method may comprise at least one more connecting flex for providing a direct current power between the second and first parts.
According further to the second aspect of the invention, the first part or the second part may be combined with the at least one connecting flex as one part and the one part may be made from a plastic flexible material. Further, the at least one connecting flex may be made of a plastic flexible material and may comprise at least one flexible electrically conducting strip. Still further, the radio frequency signal may be provided to the radiating element or to the further radiating element through the at least one flexible electrically conducting strip, wherein a feed arrangement for the radio frequency signal is provided to the at least one flexible electrically conducting strip using a feed pad on the first or second part. Yet still further, the radio frequency signal may be provided to the radiating element or to the further radiating element through the at least one flexible electrically conducting strip using a direct electrical connection between the at least one flexible electrically conducting strip and a printed wiring board of the first part or a further printed wiring board of the second part, respectively, but without connecting the at least one flexible electrically conducting strip to an RF ground of the printed wiring board or the further printed wiring board, respectively. Further still, the at least one flexible electrically conducting strip may be made of copper.
According still further to the second aspect of the invention, the electronic device may be a mobile terminal, a portable communication device, a wireless device, a mobile communication device, a mobile phone or a mobile device for wireless communications in cellular or non-cellular systems.
According to a third aspect of the invention, an apparatus, comprises: a first part comprising a radiating element; a second part comprising a further radiating element, wherein the first and second parts are configured to move relative to each other during operation; and at least one connecting means, for providing a flexible connection between the first and second parts, for providing a radio frequency signal between the radiating element and the further radiating element during the operation.
Further according to the third aspect of the invention, the at least one connecting means may be at least one connecting flex made from a plastic flexible material.
For a better understanding of the nature and objects of the present invention, reference is made to the following detailed description taken in conjunction with the following drawings, in which:
a and 2b are schematic representations of a wide connecting flex (top and side view respectively), according to an embodiment of the present invention.
a and 3b are schematic representations of a feed arrangement in the first (lower) part of the mobile terminal in a closed position (
a-5e are schematic representations of different feed arrangements in the first (lower) part of the mobile terminal, according to various embodiments of the present invention.
A new apparatus and method are presented for antenna arrangement by providing a feed arrangement through a flex connection for radiating elements of a first part and a second part (e.g., lower and upper parts, respectively) of a mobile terminal (e.g., a slide-type terminal), wherein the first and second parts are configured to move relative to each other during operation of the mobile terminal, according to an embodiment of the present invention. For a slide-type terminal, the first and the second parts can be sliding relative to each other during said operation. This antenna arrangement can be used by any of the cellular or non-cellular wireless systems. The mobile terminal can be (but is not limited to); an electronic device, a portable communication device, a wireless device, a mobile communication device, a mobile phone, a mobile device, etc.
Thus, according to various embodiments described herein, a radio frequency (RF) signal feed arrangement is used in such a way that the two parts of the mobile terminal are being driven against each other (instead of driving the antenna element against the ground plane). The two parts of the mobile terminal together are considered to be the antenna which is equivalent to feeding the two arms of a dipole antenna against each other.
According to an embodiment of the present invention, the mobile terminal can comprise at least one connecting flex, for providing a flexible connection between said first and second parts and for providing a radio frequency signal between the radiating elements of the first and second parts during said operation. According to a further embodiment, the radiating element and the further radiating elements can be ground planes or generally printed wiring boards (PWBs) or flexible wiring boards comprising said ground planes and any metal parts attached to these. The radiating element and the further radiating elements can also be parts or sections of the PWB or flexible ground planes or any metal parts attached to these. In addition, the radiating element and the further radiating elements can be essentially asymmetric. The at least one connecting flex can be made of a plastic flexible material and can comprise at least one flexible electrically conducting strip. For example, this connecting flex can be made of multiple layers of thin flexible plastic (such as polyimide) between which there are thin flexible conducting strips (e.g., made of copper). Alternatively, the connection can be made with a flexible electrically conducting wire. The flexible conducting strips (e.g., copper lines) can be used to convey signals and power between the first and second parts. The mobile device can comprise at least one more connecting flex providing, for example, short circuiting or grounding between the first and the second parts (e.g., between the radiating elements or ground planes of the first and second parts) for providing a direct current (DC) power between the second and first parts. The shorting or grounding connection might have some discrete components to modify the coupling between the radiating elements of the upper and lower parts. As shown in
It is further noted that alternatively, according to an embodiment of the present invention, one radiating element (e.g., the printed wiring board) of the first or the second part 12 or 14 can be made of the flex material and combined with the connecting flex 16 as one part, wherein said one part is made from a plastic flexible material such that the connection 20a is not needed. In this case, the RF connection to the part 14 is already in place.
There are several ways to implement the connection 20a and/or 20b, according to further embodiments described herein.
The feed arrangement according to embodiments of the present invention, described herein, can be called dipole-like feeding or direct feeding.
The example of
It is noted that the antenna feed e.g., the feed connection 20a can be followed by a matching circuit to better match the antenna input impedance to the characteristic impedance of the transmission line feeding the antenna. The role of the matching circuit is to change the impedance of the antenna to something that is close to the impedance of the transmission line in order to avoid reflections from impedance discontinuities. There could be a tunable or switchable matching circuit that could compensate for the changing impedances when the terminal device is closed. The matching circuit can be constructed of discrete components (e.g. capacitors, inductors, resistors) or sections of a transmission line.
According to another embodiment of the present invention, an alternative approach for the feed connection 20a is to connect metallization on the connecting flex 16 directly to the PWB (printed wiring board) of the first part 12 at a feed point that is then connected to the RF engine through the signal lines inside the PWB. The critical point here is that the connecting flex 16 is not connected to the RF ground of the PWB of the first part 12.
It is noted that the antenna arrangement described herein may not require any extra space for the antenna, as the wiring boards of the first (lower) and second (upper) parts of the device are used as the radiating elements. The antenna arrangement can be very broadband when the slide-type mobile terminal (device) is in the open position. However, according to current knowledge, the current antenna arrangement might be quite narrowband when the slide-type mobile terminal is in the closed position. Also, it is noted that the mobile terminals might have a combination of traditional antennas and the antenna arrangement described in various embodiments herein.
The flow chart of
In a next step 42, an RF signal, e.g., incoming phone call or digital data transmit, is received by the device using the dipole-like antenna when the device is in a closed position. In a next step 44, the upper part is moved to an open position, and a connection for the incoming call is made. In a next step 46, a further RF signal supporting the communication is sent and received using the dipole-like antenna. In a next step 48, the communication is finished, and the upper part is moved back to a closed position; then the dipole-like antenna is ready for receiving the RF signals (e.g., another phone call).
It is further noted that various embodiments of the present invention recited herein can be used separately, combined or selectively combined for specific applications.
It is to be understood that the above-described arrangements are only illustrative of the application of the principles of the present invention. Numerous modifications and alternative arrangements may be devised by those skilled in the art without departing from the scope of the present invention, and the appended claims are intended to cover such modifications and arrangements.
