EP3190661B1

EP3190661B1 - Communication terminal

Info

Publication number: EP3190661B1
Application number: EP14902918.3A
Authority: EP
Inventors: Chien-Ming Lee; Hanyang Wang; Jianren Huang; Haowei XU
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2014-09-30
Filing date: 2014-09-30
Publication date: 2019-06-05
Anticipated expiration: 2034-09-30
Also published as: EP3190661A4; WO2016049851A1; CN105940551B; EP3190661A1; CN105940551A

Description

TECHNICAL FIELD

The present invention relates to communications technologies, and in particular, to a communications terminal.

BACKGROUND

Development and application of communications technologies impose increasingly high requirements on a terminal, and especially, require a terminal antenna to have good radiation efficiency and performance.
According to a theory and practical experience, when an area with strong electric field strength distributed of the terminal antenna approaches a human head or hand, loss and attenuation may occur due to contact with the head or hand, which reduces the radiation efficiency and performance of the antenna.
In an existing communications terminal, an inverted F antenna (Inverted F Antenna, IFA for short), or a planar inverted F antenna (Planar Inverted F Antenna, PIFA for short), or the like is generally used as a terminal antenna. Because the IFA or PIFA itself is asymmetric, impact on the terminal antenna is different when the terminal is approached by a left side of a head or by a left hand and when the terminal is approached by a right side of the head or by a right hand.
US 2013/307740 A1 describes an active differential antenna that provides for improved performance for wireless communication systems across a wide set of use cases and environments. A balanced antenna structure along with switch assembly provides the differential mode radiation which results in minimal coupling to the components and items in the near field of the antenna. This results in an efficient antenna that is well isolated from the local environment of the antenna. The switch assembly is configured to switch the feed and ground connections of the differential design when needed to provide similar antenna performance for both "against head left" and "against head right" use cases for a cellular handset application for example. An active component or circuit can be integrated or coupled to the antenna design to provide the capability to dynamically balance the antenna to maintain pattern symmetry and efficiency.
WO 2013/005080 A1 discloses an apparatus comprising: a first port configured to couple to a first location on an antenna; a second port configured to couple to a second location on the antenna; a switch configured to switch between a first electrical configuration in which the first port is coupled to radio circuitry, and a second electrical configuration in which the second port is coupled to the radio circuitry; first reactive circuitry configured to impedance match the antenna with the radio circuitry at a first operational resonant frequency band; and second reactive circuitry, different to the first reactive circuitry, and configured to impedance match the antenna with the radio circuitry at a second operational resonant frequency band, different to the first operational resonant frequency band.
EP 2 597 724 A1 shows a portable communication device (100) that includes an appearance (110), a substrate (120) and a switchable resonant antenna (130). The substrate is disposed in the appearance, and the substrate has a ground plane (122). The switchable resonant antenna comprises a first connection portion (132), a switching unit (134), a first metal element (136) and a second metal element (138), where the first connection portion is electrically coupled between the ground plane and the switching unit, the switching unit is configured to electrically couple the first connection portion to the first metal element or the second metal element according to a control signal generated corresponding to a detecting result, in order to generate a first resonant mode.
US 2013/147672 A1 discloses antenna systems comprising modal antennas for use in diversity and similar schemes include a modal antenna capable of multiple antenna modes wherein a distinct radiation pattern exists for each antenna mode, and a control signal for directing variation of the antenna modes. Methods for designing modal diversity antennas are further disclosed.
JP 2012 186562 provides an antenna device comprising a first conductor, a second conductor, a feeding portion, and a switch. The first conductor is planar and includes an opening. The second conductor crosses an extended surface obtained by virtually extending the surface of the first conductor to the opening. The feeding portion supplies the second conductor with electric power. The switch varies orientation of a current flowing through the second conductor. A vector sum of the current flowing through the second conductor and a current induced by the first conductor varies according to switching of the switch.
US 2008/266190 A1 provides an antenna device configured to be fed at a feed portion included in a printed board of a radio apparatus. The antenna device has a feed element connected to the feed portion. The antenna device has a first parasitic element at least a portion of which is arranged close and electrically coupled to at least a portion of the feed element. The first parasitic element is loaded with a first frequency shifter. The antenna device has a second parasitic element at least a portion of which is arranged close and electrically coupled to at least a portion of the feed element. The second parasitic element is loaded with a second frequency shifter.

SUMMARY

According to the present application, the above objects are solved by the claimed matter according to independent claim 1. The embodiments that do not fall within the scope of the claims shall be treated as examples. The present invention provides a communications terminal, to resolve a problem in the prior art that performance is different when the terminal is approached by a left side of a head or by a left hand and when the terminal is approached by a right side of the head or by a right hand.
According to a second aspect of the embodiments of the present invention, a communications terminal is provided, including:

a feed terminal, a ground terminal, an antenna, and a single-pole double-throw switch, where the antenna includes an inverted T-shape part, a first sub-antenna, and a second sub-antenna, and the inverted T-shape part includes a horizontal bar and a vertical leg;
the feed terminal is electrically connected to a feed circuit in the communications terminal, and the ground terminal is electrically connected to a ground end in the communications terminal;
the vertical leg of the inverted T-shape part is electrically connected to the feed terminal;
the first sub-antenna and the second sub-antenna are respectively disposed on two sides of the vertical leg such that the first sub-antenna (31) and the second sub-antenna (32) are oppositely disposed relative to the vertical leg; and
a fixed end of the single-pole double-throw switch is electrically connected to the ground terminal; a first contact end of the single-pole double-throw switch is electrically connected to the first sub-antenna, and a second contract end of the single-pole double-throw switch is electrically connected to the second sub-antenna.

In a first possible implementation manner, according to the second aspect, the antenna further includes a first inductor;
the first inductor is disposed between the first sub-antenna and the first contact end.
In a second possible implementation manner, according to the second aspect, the antenna further includes a second inductor;
the second inductor is disposed between the second sub-antenna and the second contact end.
The embodiments of the present invention provide the communications terminal, including a feed terminal, a ground terminal, an antenna, and a switch part, where the antenna is an asymmetric structure; the feed terminal is electrically connected to a feed circuit in the terminal, and the ground terminal is electrically connected to a ground end in the terminal; the switch part is configured to switch between a first connection manner and a second connection manner; the first connection manner includes electrically connecting the feed terminal to a first end of the antenna, and electrically connecting the ground terminal to a second end of the antenna; and the second connection manner includes electrically connecting the ground terminal to the first end of the antenna, and electrically connecting the feed terminal to the second end of the antenna. The communications terminal includes only one feed terminal and one ground terminal, and therefore a quantity of pads can be reduced. Moreover, when the terminal is approached by a left side of a head or by a left hand, or is approached by a right side of the head or by a right hand, the switch part may be used to switch to a different connection manner, so that the communications terminal may be applicable to different holding manners of the left hand and the right hand, or may be applicable to different head approach postures. This ensures that impact on the communications terminal is similar when the communications terminal is approached by the left side of the head or by the left hand and when the communications terminal is approached by the right side of the head or by the right hand, and further ensures similar performance gains of the communications terminal.

BRIEF DESCRIPTION OF DRAWINGS

To describe the technical solutions in the embodiments of the present invention or in the prior art more clearly, the following briefly describes the accompanying drawings required for describing the embodiments or the prior art. Apparently, the accompanying drawings in the following description show some embodiments of the present invention, and persons of ordinary skill in the art may still derive other drawings from these accompanying drawings without creative efforts.

FIG. 1a is a schematic structural diagram of a communications terminal according to Embodiment 1 of the present invention;
FIG. 1b is a schematic structural diagram of another communications terminal according to Embodiment 1 of the present invention;
FIG. 2a is a schematic structural diagram of a communications terminal according to Embodiment 2 of the present invention;
FIG. 2b is a schematic diagram of electric field strength distribution of a ring antenna of a symmetric structure;
FIG. 2c is a schematic structural diagram of another communications terminal according to Embodiment 2 of the present invention;
FIG. 2d is a schematic structural diagram of still another communications terminal according to Embodiment 2 of the present invention;
FIG. 2e is a schematic structural diagram of yet another communications terminal according to Embodiment 2 of the present invention;
FIG. 3a is a schematic structural diagram of a communications terminal according to Embodiment 3 of the present invention;
FIG. 3b is a schematic structural diagram of a communications terminal according to Embodiment 3 of the present invention;
FIG. 3c is a schematic diagram of performance when a communications terminal provided in Embodiment 3 of the present invention is used in a left hand; and
FIG. 3d is a schematic diagram of performance when a communications terminal provided in Embodiment 3 of the present invention is used in a right hand.

DESCRIPTION OF EMBODIMENTS

To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the following clearly and completely describes the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by persons of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.
FIG. 1a is a schematic structural diagram of a communications terminal 1 according to Embodiment 1 of the present invention. As shown in FIG. 1a, a communications terminal 1 includes: a feed terminal 10, a ground terminal 11, an antenna 12, and a switch part 13.
Specifically, the feed terminal 10 is electrically connected to a feed circuit in the communications terminal, and the ground terminal 11 is electrically connected to a ground end in the communications terminal. The communications terminal herein may be a mobile device, a user terminal, a wireless communications device, and the like. In addition, it should be noted that, "terminal" mentioned in a context always refers to the communications terminal. The feed circuit herein is configured to process a transmit signal generated by a transmitter in the terminal and provide the signal to the communications terminal 1, and after the communications terminal 1 receives the signal, process the received signal and send the signal to a receiver in the terminal.
The antenna 12 is an asymmetric structure. Optionally, a ring antenna of an asymmetric structure may be used to implement the foregoing antenna 12.
The switch part 13 is configured to switch between a first connection manner and a second connection manner. The first connection manner includes electrically connecting the feed terminal 10 to a first end 120 of the antenna 12, and electrically connecting the ground terminal 11 to a second end 121 of the antenna 12; the second connection manner includes electrically connecting the ground terminal 11 to the first end 120 of the antenna 12, and electrically connecting the feed terminal 10 to the second end 121 of the antenna 12.
The foregoing first connection manner and second connection manner respectively correspond to FIG. 1a and FIG. 1b. To enable the switch part 13 to switch between the two connection manners, during implementation, two ends of the switch part 13 that are respectively connected to the feed terminal 10 and ground terminal 11 serve as fixed ends, and two ends of the switch part 13 that are respectively connected to the first end 120 and the second end 121 of the antenna 12 serve as contact ends. Certainly, the two ends of the switch part 13 that are respectively connected to the feed terminal 10 and ground terminal 11 may serve as contact ends, and the two ends of the switch part 13 that are respectively connected to the first end 120 and the second end 121 of the antenna 12 may serve as fixed ends. Principles of the foregoing two manners are similar. Subsequent embodiments are described in detail mainly by using the first type as an example.
Specifically, in FIG. 1a, the first end 120 of the antenna 12 is electrically connected to one of the two contact ends of the switch part 13, thereby being connected to the feed terminal 10; the second end 121 of the antenna 12 is electrically connected to the other one of the two contact ends of the switch part 13, thereby being connected to the ground terminal 11; in FIG. 1b, the first end 120 of the antenna 12 is electrically connected to one of the two contact ends of the switch part 13, thereby being connected to the ground terminal 11; the second end 121 of the antenna 12 is electrically connected to the other one of the two contact ends of the switch part 13, thereby being connected to the feed terminal 10.
Loss and attenuation may occur due to contact with a human head or hand when an area with strong electric field strength distributed of the terminal antenna is approached by the head or hand; impact on the terminal antenna is different because a manner of holding the terminal by a left hand and a manner of holding the terminal by a right hand are different or because head postures of approaching the terminal are different; as a result, performance is different when the terminal is approached by a left side of the head or by the left hand and when the terminal is approached by a right side of the head or by the right hand. By using the communications terminal 1 provided in this embodiment, due to the asymmetric structure of the antenna 12, a connection between the antenna 12 and the feed terminal 10 and that between the antenna 12 and the ground terminal 11 are different when the switch part 13 is switched between the first connection manner and the second connection manner, that is, different electric field strength distribution is caused on the antenna 12. In this way, different holding manners of the left hand and the right hand or different head approach postures can be matched, so that by switching a connection manner, it is ensured that impact on the communications terminal 1 is similar when the communications terminal 1 is approached by the left side of the head or by the left hand and when the communications terminal 1 is approached by the right side of the head or by the right hand, and further ensures similar performance gains of the communications terminal 1.
For example, when the left hand holds an existing communications terminal or when the existing communications terminal is approached by the left side of the head, assuming that an area with strong electric field strength distributed of an antenna of the terminal is a holding position of the left hand, performance of the terminal antenna is poor. When the right hand holds the existing communications terminal or when the existing communications terminal is approached by the right side of the head, because the area with strong electric field strength distributed of the antenna of the terminal is the holding position of the left hand or a position in which the existing communications terminal is approached by the left side of the head, impact on the existing communications terminal is small and performance is relatively good. This is the difference in impact on the existing communications terminal caused by a difference of holding manners or a difference of head approach postures. In comparison, when the left hand holds the communications terminal 1 or when the communications terminal 1 is approached by the left side of the head, because an area with strong electric field strength distributed of the antenna 12 of the communications terminal 1 is a holding position of the left hand or a position in which the communications terminal 1 is approached by the left side of the head, the switch part 13 of the communications terminal 1 may be disposed in a position which enables the area with strong electric field strength distributed of the antenna 12 to be far from the holding position of the left hand or the position in which the communications terminal 1 is approached by the left side of the head, and in this case, performance of the communications terminal 1 is relatively good. When the right hand holds the communications terminal 1 or when the communications terminal 1 is approached by the right side of the head, because the area with strong electric field strength distributed of the antenna 12 of the communications terminal 1 is the holding position of the left hand or the position in which the communications terminal 1 is approached by the left side of the head, the switch part 13 of the communications terminal 1 may be disposed in a position which enables the area with strong electric field strength distributed of the antenna 12 to be far from a holding position of the right hand or a position in which the communications terminal 1 is approached by the right side of the head, and in this case, the performance of the communications terminal 1 is also relatively good. This ensures that impact on the communications terminal 1 is similar when the terminal is approached by the left side of the head or by the left hand and when the terminal is approached by the right side of the head or by the right hand, and further ensures similar performance gains of the communications terminal 1.
A change of field strength distribution of the antenna 12 is specifically used below to explain the foregoing process.
When the switch part 13 is switched to the first connection manner shown in FIG. 1a, strongest electric field distribution points, of a first mode (Low Band, LB for short), a second mode (High Band1, HB1 for short), and a third mode (High Band2, HB2 for short), used to represent radiation efficiency of the antenna 12 are all shown in FIG. 1a by using small blocks. When the switch part 13 is switched to the second connection manner shown in FIG. 1b, strongest electric field distribution points, of LB, HB1, and HB2, used to represent the radiation efficiency of the antenna 12 are all shown in FIG. 1b by using small blocks. It may be seen that, electric field strength distribution of the antenna 12 is different in these two working states. Therefore, in practice, when the communications terminal 1 is approached by the left side of the head or by the left hand, the switch part 13 is switched to the connection manner shown in FIG. 1a. When the communications terminal 1 is approached by the right side of the head or by the right hand, the switch part 13 is switched to the connection manner shown in FIG. 1b. This ensures same impact on the communications terminal 1 in different holding manners of the left hand and the right hand or caused by different head approach postures, and further ensures similar performance gains of the communications terminal 1. Certainly, electric field strength distribution may be different for the antenna 12 of different asymmetric structures. Therefore, a shape of the antenna 12 may be determined according to actually required radiation efficiency of the communications terminal 1.
This embodiment of the present invention provides the communications terminal, including a feed terminal, a ground terminal, an antenna, and a switch part, where the antenna is an asymmetric structure; the feed terminal is electrically connected to a feed circuit in the terminal, and the ground terminal is electrically connected to a ground end in the terminal; the switch part is configured to switch between a first connection manner and a second connection manner; the first connection manner includes electrically connecting the feed terminal to a first end of the antenna, and electrically connecting the ground terminal to a second end of the antenna; and the second connection manner includes electrically connecting the ground terminal to the first end of the antenna, and electrically connecting the feed terminal to the second end of the antenna. The communications terminal includes only one feed terminal and one ground terminal, and therefore a quantity of pads can be reduced. Moreover, when the terminal is approached by a left side of a head or by a left hand, or is approached by a right side of the head or by a right hand, the switch part may be used to switch to a different connection manner, so that the communications terminal may be applicable to different holding manners of the left hand and the right hand, or may be applicable to different head approach postures. This ensures that impact on the communications terminal is similar when the communications terminal is approached by the left side of the head or by the left hand and when the communications terminal is approached by the right side of the head or by the right hand, and further ensures similar performance gains of the communications terminal.
FIG. 2a is a schematic structural diagram of a communications terminal according to Embodiment 2 of the present invention. As shown in FIG. 2a, a communications terminal 2 includes a feed terminal 10, a ground terminal 11, an antenna 20, and a switch part 13, where the antenna 20 includes a ring antenna 21 of a symmetric structure and an inductor 22. The communications terminal 2 further includes a sensor 23 and a controller 24.
Specifically, the feed terminal 10 is electrically connected to a feed circuit in the terminal, and the ground terminal 11 is electrically connected to a ground end in the terminal. The communications terminal herein may be a mobile device, a user terminal, a wireless communication device, and the like.
The feed terminal 10 is electrically connected to a first end 200 of the antenna 20, and the ground terminal 11 is electrically connected to a second end 201 of the antenna 20; the inductor 22 is disposed between the feed terminal 10 and the first end 200 of the antenna 20; one of two fixed ends of the switch part 13 is electrically connected to the feed terminal 10 while the other is electrically connected to the ground terminal 11; one of two contact ends of the switch part 13 is electrically connected to the first end 200 of the antenna 20, that is, a first end of the ring antenna 21 of the symmetric structure while the other is electrically connected to the second end 201 of the antenna 20, that is, a second end of the ring antenna 21 of the symmetric structure.
The sensor 23 is configured to detect a left hand status and a right hand status, and the controller 24 is separately connected to the sensor 23 and the switch part 13, and is configured to control, according to a detection result of the sensor 23, the switch part 13 to switch to a connection manner that matches the detection result. The sensor may be a voltage-sensitive sensor, an accelerometer, a gyroscope, a magnetometer, an optical proximity sensor, and the like.
For ease of comparison, FIG. 2b shows a diagram of electric field strength distribution of the ring antenna 21 of the symmetric structure when an inductor is not added. In addition, FIG. 2b has no switch part, while FIG. 2a has the switch part 13 and is a diagram of electric field strength distribution after the inductor 22 is disposed between the feed terminal 10 and the first end 200 of the antenna 20. A structure in FIG. 2c is similar to that in FIG. 2a, but the switch part 13 in FIG. 2c is switched to a second connection manner, where in this case, the inductor 22 is disposed between the feed terminal 10 and the second end 201 of the antenna 20. It may be learned by comparing FIG. 2a with FIG. 2b that, before the inductor 22 is added, electric field strength of the ring antenna 21 is evenly distributed; therefore, performance is different when the communications terminal 2 is approached by a left side of a head or by a left hand and when the communications terminal 2 is approached by a right side of the head or by a right hand, where the difference is caused by a difference between a manner of holding the communications terminal 2 in the left hand and a manner of holding the communications terminal 2 in the right hand, or a difference between head approach postures. After the inductor 22 is added, the electric field strength is no longer evenly distributed; similar to the foregoing description, in FIG. 2a, the first end 200 of the antenna 20 is electrically connected to one of the two contact ends of the switch part 13, thereby being connected to the feed terminal 10, and the second end 201 is electrically connected to the other one of the two contact ends of the switch part 13, thereby being connected to the ground terminal 11. In FIG. 2c, the first end 200 of the antenna 20 is electrically connected to one of the two contact ends of the switch part 13, thereby being connected to the ground terminal 11, and the second end 201 of the antenna 20 is electrically connected to the other one of the two contact ends of the switch part 13, thereby being connected to the feed terminal 10. In this case, though the ring antenna 21 is a symmetric structure, because the inductor 22 is further disposed in the communications terminal 2, the inductor 22 can affect electric field strength distribution of the ring antenna 21, so that electric field strength distribution of the antenna 20 becomes uneven on the whole.
For example, when the switch part 13 is switched to the connection manner shown in FIG. 2a, strongest electric field distribution points, of LB, HB1, and HB2, that represent radiation efficiency of the ring antenna 21 are all shown in FIG. 2a by using small blocks. When the switch part 13 is in the connection manner shown in FIG. 2c, strongest electric field distribution points, of LB, HB1, and HB2, that represent the radiation efficiency of the ring antenna 21 are all shown in FIG. 2c by using small blocks. It may be learned that, electric field strength distribution of the ring antenna 21 is different in these two working states. Therefore, in practice, the sensor 23 can detect the left hand status and the right hand status. When the left hand holds the communications terminal 2 or when the communications terminal 2 is approached by the left side of the head, the detection result is sent to the controller 24 and the controller 24 may control the switch part 13 according to the detection result, so that the switch part 13 is switched to the connection manner shown in FIG. 2a. When the right hand holds the communications terminal 2 or when the communications terminal 2 is approached by the right side of the head, the controller 24 controls the switch part 13, so that the switch part 13 is switched to the connection manner shown in FIG. 2c. In this way, different holding manners of the left hand and the right hand or different head approach postures can be matched, so that by switching a connection manner, it is ensured that impact on the communications terminal 2 is similar when the communications terminal 2 is approached by the left side of the head or by the left hand and when the communications terminal 2 is approached by the right side of the head or by the right hand, and further ensures similar performance gains of the communications terminal 2. In practice, a value of the inductor 22 is determined by a working frequency of the communications terminal 2.
Optionally, by switching the switch part 13, the inductor 22 may be further disposed between the ground terminal 11 and the first end 200 of the antenna 20 or the second terminal 201 of the antenna 20. For a specific connection relationship and field strength distribution thereof, refer to FIG. 2d and FIG. 2e, where working principles thereof are similar with those of FIG. 2c and FIG. 2a, which are not described herein again.
This embodiment of the present invention provides the communications terminal, including a feed terminal, a ground terminal, an antenna, and a switch part, where the antenna is an asymmetric structure; the feed terminal is electrically connected to a feed circuit in the terminal, and the ground terminal is electrically connected to a ground end in the terminal; the switch part is configured to switch between a first connection manner and a second connection manner; the first connection manner includes electrically connecting the feed terminal to a first end of the antenna, and electrically connecting the ground terminal to a second end of the antenna; and the second connection manner includes electrically connecting the ground terminal to the first end of the antenna, and electrically connecting the feed terminal to the second end of the antenna. This embodiment of the present invention provides the communications terminal, including a feed terminal, a ground terminal, an antenna, and a switch part, where the antenna is an asymmetric structure; the feed terminal is electrically connected to a feed circuit in the terminal, and the ground terminal is electrically connected to a ground end in the terminal; the switch part is configured to switch between a first connection manner and a second connection manner; the first connection manner includes electrically connecting the feed terminal to a first end of the antenna, and electrically connecting the ground terminal to a second end of the antenna; and the second connection manner includes electrically connecting the ground terminal to the first end of the antenna, and electrically connecting the feed terminal to the second end of the antenna. The communications terminal includes only one feed terminal and one ground terminal, and therefore a quantity of pads can be reduced. Moreover, when the terminal is approached by a left side of a head or by a left hand, or is approached by a right side of the head or by a right hand, the switch part may be used to switch to a different connection manner, so that the communications terminal may be applicable to different holding manners of the left hand and the right hand, or may be applicable to different head approach postures. This ensures that impact on the communications terminal is similar when the communications terminal is approached by the left side of the head or by the left hand and when the communications terminal is approached by the right side of the head or by the right hand, and further ensures similar performance gains of the communications terminal.
FIG. 3a is a schematic structural diagram of a communications terminal according to Embodiment 3 of the present invention. As shown in FIG. 3a, a communications terminal 3 includes: a feed terminal 10, a ground terminal 11, an antenna 12, and a single-pole double-throw switch 13. The antenna 12 includes a T-shape part 30, a first sub-antenna 31, and a second sub-antenna 32.
Specifically, the feed terminal 10 is electrically connected to a feed circuit in the communications terminal, and the ground terminal 11 is electrically connected to a ground end in the communications terminal. The communications terminal herein may be a mobile device, a user terminal, a wireless communication device, and the like. The feed circuit herein is configured to process a transmit signal generated by a transmitter in the terminal and provide the signal to the communications terminal 3, and after the communications terminal 3 receives the signal, process the received signal and send the signal to a receiver in the terminal.
The inverted T-shape part 30 includes a horizontal bar and a vertical leg. The vertical leg of the inverted T-shape part 30 is electrically connected to the feed terminal 10. The first sub-antenna 31 and the second sub-antenna 32 are respectively disposed on two sides of the vertical leg. A fixed end of the single-pole double-throw switch 13 is electrically connected to the ground terminal 11. A first contact end 130 of the single-pole double-throw switch 13 is electrically connected to the first sub-antenna 31, and a second contact end 131 of the single-pole double-throw switch 13 is electrically connected to the second sub-antenna 32.
FIG. 3b is a schematic structural diagram of a communications terminal according to Embodiment 3 of the present invention. Compared with that in FIG. 3a, the single-pole double-throw switch 13 is in another connection manner. The first sub-antenna 31 and the second sub-antenna 32 are oppositely disposed in relative to the vertical leg of the inverted T-shape part 30. Therefore, when the single-pole double-throw switch 13 is in a state shown in FIG. 3a, the first sub-antenna 31 is connected between the feed terminal 10 and the ground terminal 11. Because the first sub-antenna 31 is disposed on a left side, in practice, such disposition is more suitable for a behavior that a left hand holds the communications terminal or the communications terminal is approached by a left side of a head, where in this case, the other four fingers except the thumb are on a right side, and therefore impact on the communications terminal 3 is small. When the single-pole double-throw switch 13 is in the connection manner shown in FIG. 3b, the second sub-antenna 32 is connected between the feed terminal 10 and the ground terminal 11. Because the second sub-antenna 32 is disposed on the left side, in practice, such disposition is more suitable for a behavior that a right hand holds the communications terminal or the communications terminal is approached by a right side of the head, where in this case, the other four fingers except the thumb are on the left side, and therefore impact on the communications terminal 3 is small. In this way, the communications terminal 3 can be applicable to different holding manners of the left hand and the right hand or different head approach postures in using different connection manners of the single-pole double-throw switch 13, that is, by switching a manner of a ground leg of the sub-antennas. This ensures that impact on the communications terminal 3 is similar when the communications terminal 3 is approached by the left side of the head or by the left hand and when the communications terminal 3 is approached by the right side of the head or by the right hand, and further ensures similar performance gains of the communications terminal 3.
Optionally, as shown in FIG. 3a, the first sub-antenna 31 may be a metal conducting line that is disposed for a distance on a direction parallel with the horizontal bar and departing from the second sub-antenna 32 and that is electrically connected to the first contact end 130 of the single-pole double-throw switch 13 after being bent twice; the second sub-antenna 32 may be a metal conducting line that is disposed for a distance on a direction parallel with the horizontal bar and departing from the first sub-antenna 31 and that is electrically connected to the second contact end 131 of the single-pole double-throw switch 13 after being bent twice. The metal conducting line, in the first sub-antenna 31, parallel with the horizontal bar of the inverted T-shape part 30 is in a horizontal relationship with the horizontal bar. This is equivalent to forming a capacitor, and a bent part of the metal conducting line of the first sub-antenna 31 is equivalent to a formed inductor; therefore, the capacitor and the inductor may form resonate, thereby implementing radiation of an electromagnetic wave by the first sub-antenna 31. For the second sub-antenna 32, a principle thereof is similar. The first sub-antenna 31 is used as an example. Because a vertical distance from the metal conducting line, in the first sub-antenna 31, parallel with the horizontal bar to the horizontal bar may affect capacitive reactance of the foregoing capacitor, the foregoing vertical distance may be generally determined according to a working frequency of the communications terminal 3. Likewise, a principle of the second sub-antenna 32 is similar, and a vertical distance from the metal conducting line, of the second sub-antenna 32, parallel with the horizontal bar to the horizontal bar may also be determined according to a working frequency of the communications terminal 3. It should be noted that, in FIG. 3a and FIG. 3b, structures of the first sub-antenna 31 and the second sub-antenna 32 are merely examples. In actual application, a quantity of bending times of the foregoing metal conducting line, the foregoing vertical distance to the horizontal bar, and the like may all be determined according to the working frequency of the communications terminal 3. In addition, the first sub-antenna 31 and the second sub-antenna 32 may be symmetrically or asymmetrically disposed on the two sides of the vertical leg of the inverted T-shape part 30.
Optionally, the communications terminal 3 may further include a first inductor 34, where the first inductor 34 is disposed between the first sub-antenna 31 and the first contact end 130, and a function of the first inductor 34 is similar to an inductor function of the first sub-antenna 31 itself, and an actual value of the first inductor 34 may be determined according to the working frequency of the communications terminal 3.
Optionally, the communications terminal 3 may further include a second inductor 35, where the second inductor 35 is disposed between the second sub-antenna 32 and the second contact end 131, and a function of the second inductor 35 is similar to an inductor function of the second sub-antenna 32 itself, and an actual value of the second inductor 35 may be determined according to the working frequency of the communications terminal 3.
Optionally, the communications terminal 3 may further include a sensor 36 and a controller 37. The sensor 36 is configured to detect a left hand status and a right hand status, and the controller 37 is separately connected to the sensor 36 and the single-pole double-throw switch 13, and is configured to control, according to a detection result of the sensor 36, the single-pole double-throw switch 13 to switch to a connection manner that matches the detection result. The sensor 36 and the controller 37 are not shown in FIG. 3a and FIG. 3b, and specific connections thereof are similar to those in FIG. 2a, which are not described herein again.
FIG. 3c is a schematic diagram of performance when a communications terminal provided in Embodiment 3 of the present invention is used in a left hand; and FIG. 3d is a schematic diagram of performance when a communications terminal provided in Embodiment 3 of the present invention is used in a right hand. A horizontal axis represents a frequency; a vertical axis represents a performance gain of the communications terminal 3; a solid line represents a performance gain of the single-pole double-throw switch 13 when it is in the state shown in FIG. 3a; a dotted line represents a performance gain of the single-pole double-throw switch 13 when it is in the state shown in FIG. 3b. It may be learned that, from 894 MHz to 2190 MHz, that is, at a frequency band of the Global System for Mobile Communications (Global System for Mobile communication, GSM for short) and Long Term Evolution (Long Term Evolution, LTE for short), performance is similar when the communications terminal 3 is used in the left hand and when the communications terminal 3 is used in the right hand.
This embodiment of the present invention provides the communications terminal, including a feed terminal, a ground terminal, an antenna, and a single-pole double-throw switch, where the antenna includes an inverted T-shape part, a first sub-antenna, and a second sub-antenna; the feed terminal is electrically connected to a feed circuit in the communications terminal, and the ground terminal is electrically connected to a ground end in the communications terminal; a vertical leg of the inverted T-shape part is electrically connected to the feed terminal; the first sub-antenna and the second sub-antenna are respectively disposed on two sides of the vertical leg. A fixed end of the single-pole double-throw switch is electrically connected to the ground terminal. A first contact end of the single-pole double-throw switch is electrically connected to the first sub-antenna, and a second contact end of the single-pole double-throw switch is electrically connected to the second sub-antenna. The communications terminal includes only one feed terminal and one ground terminal, and therefore a quantity of pads can be reduced. Moreover, the communications terminal provided in this embodiment of the present invention may be applicable to different holding manners of the left hand and the right hand, or may be applicable to different head approach postures. This ensures that impact on the communications terminal is similar when the communications terminal is approached by a left side of a head or by the left hand and when the terminal is approached by a right side of the head or by the right hand, and further ensures similar performance gains of the communications terminal.

Claims

A communications terminal, comprising:
a feed terminal (10), a ground terminal (11), an antenna (12), and a single-pole double-throw switch (13), wherein the antenna comprises an inverted T-shape part (30), a first sub-antenna (31), and a second sub-antenna (32), and the inverted T-shape part (30) comprises a horizontal bar and a vertical leg;

the feed terminal (10) is electrically connected to a feed circuit in the communications terminal, and the ground terminal (11) is electrically connected to a ground end in the communications terminal;

the vertical leg of the inverted T-shape part (30) is electrically connected to the feed terminal (10); and

a fixed end of the single-pole double-throw switch (13) is electrically connected to the ground terminal (11); a first contact end (130) of the single-pole double-throw switch is electrically connected to the first sub-antenna (31), and a second contact end (131) of the single-pole double-throw switch (13) is electrically connected to the second sub-antenna (32), characterized in that the first sub-antenna (31) and the second sub-antenna (32) are respectively disposed on two sides of the vertical leg such that the first sub-antenna (31) and the second sub-antenna (32) are oppositely disposed relative to the vertical leg.
The communications terminal according to claim 1, wherein the antenna (12) further comprises a first inductor (34); and
the first inductor (34) is disposed between the first sub-antenna (31) and the first contact end (130).
The communications terminal according to claim 1 or 2, wherein the antenna further comprises a second inductor (35); and
the second inductor (35) is disposed between the second sub-antenna (32) and the second contact end (131).
The communications terminal according to any one of claims 1 to 3, wherein the communications terminal further comprises a sensor (23) and a controller (24);
the sensor (23) is configured to detect a left hand status and a right hand status; and
the controller (24) is separately connected to the sensor (23) and the single-pole double-throw switch (13), and is configured to control, according to a detection result of the sensor (23), the single-pole double-throw switch (13) to switch to a connection manner that matches the detection result.