A radio frequency circuit and a mobile terminal

Abstract

The application discloses a radio frequency circuit and a mobile terminal, wherein the radio frequency circuit comprises a first antenna, a second antenna, a radio frequency chip, a baseband chip, a first antenna tuner and a second antenna tuner; the baseband chip comprises a first port, the first port is connected with the first antenna tuner and the second antenna tuner through a first control line respectively, the radio frequency chip is connected with the first antenna and the second antenna respectively, the first antenna is connected with the first antenna tuner, and the second antenna is connected with the second antenna tuner; wherein the baseband chip is used for outputting a first control signal to the first antenna tuner and the second antenna tuner through the first port, so as to adjust the impedance of the first antenna tuner and the second antenna tuner. Through multiplexing the control line, the application can effectively reduce the wiring of the control line and save the port of the baseband chip.

Description

Technical Field

[0001] This invention relates to the field of mobile communication technology, and in particular to a radio frequency circuit and a mobile terminal. Background Technology

[0002] An antenna tuner is an active device, similar to a switch. It requires a control signal to switch the antenna tuner to different channels. This control signal comes from the baseband chip and is transmitted via control lines on the PCB. By pre-setting parameters, the baseband chip can issue different control commands to the antenna tuner switch to the corresponding channel based on the antenna's current operating frequency. This enables different impedance matching, ensuring the antenna performance matches the current operating frequency. In other words, it achieves impedance matching between the RF chip and the antenna at the current operating frequency, thereby maximizing antenna gain.

[0003] Each antenna tuning switch requires two control lines, with each control line connected to a corresponding GPIO port. In conventional designs, the control lines between each antenna tuning switch are separate, without crossing or affecting each other, allowing independent control of each switch. However, when the platform chip itself has a limited number of GPIO control ports, a shortage of GPIO ports can occur when controlling multiple antenna tuning switches.

[0004] Therefore, the existing technology still needs to be improved and enhanced. Summary of the Invention

[0005] The purpose of this invention is to provide a radio frequency circuit and a mobile terminal that, by multiplexing control lines, can effectively reduce the wiring of control lines and save ports of the baseband chip, thereby solving the problem of insufficient ports when controlling multiple tuning switches.

[0006] To achieve the above objectives, the present invention adopts the following technical solution:

[0007] This application provides a radio frequency circuit, including a first antenna, a second antenna, a radio frequency chip, a baseband chip, a first antenna tuner, and a second antenna tuner; the baseband chip includes a first port, which is connected to the first antenna tuner and the second antenna tuner respectively via a first control line; the radio frequency chip is connected to the first antenna and the second antenna respectively; the first antenna is connected to the first antenna tuner; and the second antenna and the second antenna tuner are connected.

[0008] The baseband chip is used to output a first control signal to the first antenna tuner and the second antenna tuner through the first port to adjust the impedance of the first antenna tuner and the second antenna tuner.

[0009] In some embodiments of the radio frequency circuit, the baseband chip further includes a second port, which is connected to the first antenna tuner and the second antenna tuner respectively via a second control line; the baseband chip is also used to output a second control signal to the first antenna tuner and the second antenna tuner through the second port, so that the first control signal and the second control signal jointly adjust the impedance of the first antenna tuner and the second antenna tuner.

[0010] In some embodiments of the radio frequency circuit, the baseband chip further includes a third port and a fourth port. The third port is connected to the first antenna tuner via a third control line, and the fourth port is connected to the second antenna tuner via a fourth control line. The baseband chip is also used to output a third control signal to the first antenna tuner via the third port and to output a fourth control signal to the second antenna tuner via the fourth port, so that the first control signal and the third control signal jointly adjust the impedance of the first antenna tuner and the impedance of the second antenna tuner.

[0011] In some embodiments of the radio frequency circuit, both the first port and the second port are GPIO ports.

[0012] In some embodiments of the radio frequency circuit, the first antenna tuner includes four first impedance matching channels, and the first antenna tuner is used to turn on one of the four first impedance matching channels according to a first control signal and a second control signal.

[0013] In some embodiments of the radio frequency circuit, the second antenna tuner includes four second impedance matching channels, and the second antenna tuner is used to turn on the four second impedance matching channels according to a first control signal and a second control signal.

[0014] In some embodiments of the radio frequency circuit, the first antenna tuner includes four first impedance matching channels, and the first antenna tuner is used to turn on one of the four first impedance matching channels according to a first control signal and a third control signal.

[0015] In some embodiments of the radio frequency circuit, the second antenna tuner includes four second impedance matching channels, and the second antenna tuner is used to turn on one of the second impedance matching channels according to a first control signal and a fourth control signal.

[0016] In some embodiments of the radio frequency circuit, the radio frequency chip includes a first radio frequency port and a second radio frequency port. The first radio frequency port is connected to a first antenna via a first radio frequency feed line, and the second radio frequency port is connected to a second antenna via a second radio frequency feed line.

[0017] This application also provides a mobile terminal, including the radio frequency circuit described above.

[0018] Compared to existing technologies, this invention provides a radio frequency circuit and a mobile terminal. In the radio frequency circuit, a single control line is used to control two tuners, which saves on the use of control lines and reduces wiring on the PCB board compared to using an independent control line for each tuner. This also saves on the GPIO ports of the baseband chip, thus avoiding the situation of insufficient ports when controlling multiple tuning switches. Attached Figure Description

[0019] Figure 1 This is a first structural block diagram of the radio frequency circuit provided by the present invention.

[0020] Figure 2 This is a second structural block diagram of the radio frequency circuit provided by the present invention.

[0021] Figure 3 This is a third structural block diagram of the radio frequency circuit provided by the present invention. Detailed Implementation

[0022] The purpose of this invention is to provide a radio frequency circuit and a mobile terminal that, by multiplexing control lines, can effectively reduce the wiring of control lines and save ports of the baseband chip, thereby solving the problem of insufficient ports when controlling multiple tuning switches.

[0023] To make the objectives, technical solutions, and effects of this invention clearer and more explicit, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0024] Please see Figure 1 The present invention provides a radio frequency circuit including a first antenna 11, a second antenna 12, a radio frequency chip 31, a baseband chip 32, a first antenna tuner 21, and a second antenna tuner 22. The first antenna 11 includes a first port A, which is connected to the first antenna tuner 21 and the second antenna tuner 22 respectively through a first control line 41. The radio frequency chip 31 is connected to the first antenna 11 and the second antenna 12 respectively. The first antenna 11 is connected to the first antenna tuner 21, and the second antenna 12 is connected to the second antenna tuner 22.

[0025] In this embodiment, the RF chip 31 transmits and receives RF signals through the first antenna 11 and the second antenna 12. It should be noted that in this embodiment, the RF chip 31 can be connected to three or more antennas, and each antenna is connected to a corresponding tuner; therefore, the number of tuners can also be three or more, which is not limited in this invention. The baseband chip 32 outputs a first control signal through the first port A to the first antenna tuner 21 and the second antenna tuner 22 to adjust the impedance of the first antenna tuner 21 and the second antenna tuner 22. In this embodiment, the first control signal can be either a high-level signal or a low-level signal; that is, the first control line 41 can be used to transmit both high-level and low-level signals. This first control signal is output through the first port A of the baseband chip 32 and transmitted to the first antenna tuner 21 and the second antenna tuner 22 via the first control line 41. This is equivalent to the first antenna tuner 21 and the second antenna tuner 22 multiplexing a first control line 41 and sharing a first port A. In this embodiment, the first port A is a GPIO port. Compared to using an independent control line for each tuner, this saves on the use of control lines, reduces wiring on the PCB, and thus saves on the GPIO ports of the baseband chip 32, avoiding a situation where there are not enough ports when controlling multiple tuner switches.

[0026] Please refer to the following: Figure 2 In specific implementations, each tuner requires two control lines; therefore, both the first antenna tuner 21 and the second antenna tuner 22 require an additional control line. In some embodiments, the baseband chip 32 further includes a third port C and a fourth port D. The third port C is connected to the first antenna tuner 21 via a third control line 43, and the fourth port D is connected to the second antenna tuner 22 via a fourth control line 44. The baseband chip 32 is also used to output a third control signal to the first antenna tuner 21 via the third port C and a fourth control signal to the second antenna tuner 22 via the fourth port D, so that the first and third control signals jointly adjust the impedance of the first antenna tuner 21 and the second antenna tuner 22. That is, in this embodiment, the first antenna tuner 21 and the second antenna tuner 22 reuse only one control line, and the first antenna tuner 21 and the second antenna tuner 22 are controlled by three control lines, namely the first control line 41, the third control line 43, and the fourth control line 44. Similarly, the third control signal transmitted by the third control line 43 can be a high-level signal or a low-level signal, and the fourth control signal transmitted by the fourth control line 44 can be a high-level signal or a low-level signal.

[0027] In this embodiment, the first antenna tuner 21 includes four first impedance matching channels, and the second antenna tuner 22 includes four second impedance matching channels. Specifically, the first antenna tuner 21 includes a first switch, which includes a first common terminal and four first matching terminals. The first antenna tuner 21 also includes four first matching devices connected one-to-one with the first matching terminals. The first common terminal is connected to the first antenna 11, and each first matching terminal is connected to its corresponding first matching device to form a first impedance matching channel. Similarly, the second antenna tuner 22 includes a second switch, which includes a second common terminal and four second matching terminals. The second antenna tuner 22 also includes four second matching devices connected one-to-one with the second matching terminals. The second common terminal is connected to the second antenna 12, and each second matching terminal is connected to its corresponding second matching device to form a second impedance matching channel. The first and second matching devices can be capacitors and / or inductors, and the number of capacitors and inductors can be one or more. This invention does not specifically limit the number of first and second matching devices.

[0028] The first antenna tuner 21 is used to connect one of the first impedance matching channels according to the first control signal and the third control signal. When the first antenna 11 transmits radio frequency signals of different frequency bands, the baseband chip 32 outputs the first control signal and the third control signal to control the first antenna tuner 21 to connect to the corresponding first impedance matching channel, thereby achieving impedance matching of the first antenna. The second antenna tuner 22 is used to connect one of the four second impedance matching channels according to the first control signal and the fourth control signal. When the second antenna 12 transmits radio frequency signals of different frequency bands, the baseband chip 32 outputs the first control signal and the fourth control signal to control the second antenna tuner 22 to connect to the corresponding second impedance matching channel, thereby achieving impedance matching of the second antenna.

[0029] When the first control line 41 is multiplexed, the first antenna tuner 21 is still controlled by two control lines: the first control line 41 and the third control line 43, while the second antenna tuner 22 is still controlled by two control lines: the first control line 41 and the fourth control line 44. Since each control line can transmit both high-level and low-level signals, each tuner controller can still achieve four states of control, i.e., four matching switching. Correspondingly, each antenna can transmit and receive radio frequency signals in four frequency bands. However, due to the multiplexing of the first control line 41, when the control signal of the first control line 41 changes, both the first antenna tuner 21 and the second antenna tuner 22 will switch states. That is, when the first impedance matching channel of one tuner needs to change, if this change needs to be achieved through a change in the first control signal transmitted on the multiplexed first control line 41, then the second impedance matching channel of the other tuner also needs to change accordingly. Each tuner is connected to a different antenna. When the mobile terminal operates in different frequency bands, that is, when the antenna needs to transmit and receive different radio frequency signals, due to performance requirements, the tuner on the current antenna may need to switch to a different impedance matching channel to achieve impedance matching.

[0030] If the frequency bands for the radio frequency signals transmitted and received by each antenna can be B8, B5, B20, and B28, with a high-level signal being 1 and a low-level signal being 0, then the correspondence between the four states of each tuner under the control of two control signals and the corresponding frequency bands is as follows:

[0031]

[0032] Specifically, when the frequency band of the radio frequency signal transmitted and received by the first antenna 11 is B5, the first control line 41 needs to transmit a low-level signal and the third control line 43 needs to transmit a low-level signal to the first antenna tuner 21, so that the first antenna tuner 21 is switched to the corresponding first impedance matching channel to match the operating frequency band of the first antenna 11. At this time, the first control line 41 will transmit a low-level signal to the second antenna tuner 22. If the fourth control line 44 also transmits a low-level signal at this time, the second antenna tuner 22 will switch to the corresponding second impedance matching channel to match the operating frequency band of the second antenna 12, i.e., B20. When the frequency band of the radio frequency signal transmitted and received by the first antenna 11 is B5, the control signal of the first control line 41 needs to change to a high level, and the first antenna tuner 21 switches to the corresponding first impedance matching channel. At this time, in order to adapt to the change of the control signal on the first control line 41, the control signal on the fourth control line 44 of the second antenna tuner 22 can be changed to a high-level signal, so that the second antenna tuner 22 switches the corresponding second impedance matching channel to match the radio frequency signal of the B5 band on the second antenna 12.

[0033] Please see Figure 3In some embodiments, two control lines can be reused simultaneously. Specifically, in this embodiment, the baseband chip 32 further includes a second port B, which is connected to the first antenna tuner 21 and the second antenna tuner 22 via the second control line 42. The baseband chip 32 is also used to output a second control signal to the first antenna tuner 21 and the second antenna tuner 22 via the second port B to adjust the impedance of the first antenna tuner 21 and the second antenna tuner 22. The second control signal can be a high-level signal or a low-level signal, and the second port B is a GPIO port. In this embodiment, both the first antenna tuner 21 and the second antenna tuner 22 are controlled by the first control line 41 and the second control line 42. By reusing the first control line 41 and the second control line 42, the baseband chip 32 can control two tuners using only two ports and two control lines, thereby further reducing the wiring of control lines and saving GPIO ports on the baseband chip 32.

[0034] In this embodiment, the first antenna tuner 21 includes four first impedance matching channels, and the first antenna tuner 21 is used to turn on one of the four first impedance matching channels according to the first control signal and the second control signal; the second antenna tuner 22 includes four second impedance matching channels, and the second antenna tuner 22 is used to turn on one of the four second impedance matching channels according to the first control signal and the second control signal.

[0035] At this time, the first antenna tuner 21 and the second antenna tuner 22 can still switch between four states. However, when one of the tuners switches to the first impedance matching channel, the second antenna tuner 22 also needs to switch to the second impedance matching channel accordingly.

[0036] If the frequency bands for the radio frequency signals transmitted and received by each antenna can be B8, B5, B20, and B28, with a high-level signal of 1 and a low-level signal of 0, then the correspondence between the four states of each tuner under the control of two control signals and the corresponding frequency bands in this embodiment is as follows:

[0037]

[0038] Specifically, when the frequency band of the radio frequency signal transmitted and received by the first antenna 11 is B8, the first control line 41 needs to transmit a low-level signal and the second control line 42 needs to transmit a low-level signal to the first antenna tuner 21, causing the first antenna tuner 21 to switch to the corresponding first impedance matching channel to match the operating frequency band of the first antenna 11. At this time, the first control line 41 will transmit a low-level signal and the second control line 42 will transmit a low-level signal to the second antenna tuner 22, causing the second antenna tuner 22 to switch to the corresponding second impedance matching channel to match the B8 frequency band of the second antenna 12. When the frequency band of the radio frequency signal transmitted and received by the first antenna 11 is B5, the control signal of the first control line 41 needs to change to a high level, and the first antenna tuner 21 switches to the corresponding first impedance matching channel. At this time, the second antenna tuner 22 also receives the low-level signals transmitted by the first control line 41 and the second control line 42, and then switches to the corresponding second impedance matching channel to adapt to the radio frequency signal in the B5 frequency band on the second antenna 12.

[0039] If you don't want switching the impedance matching channel in one tuner to affect another tuner, you can use the same matching device for the two impedance matching channels in the other tuner. For example, you can use a 10Nh inductor for two of the four second impedance matching channels in the second antenna tuner 22. In this way, when switching between these two impedance matching channels, although the impedance matching channel of the second antenna tuner 22 is switched, the impedance matching value connected to the antenna does not change, and the antenna performance is not affected.

[0040] It should be noted that three or more control lines can be reused in this application to control the tuner, which reduces the number of GPIO ports required for the baseband chip 32 in the mobile terminal, allowing the mobile terminal to use lower-cost chips and reduce the cost of the mobile terminal; at the same time, because the control lines are reduced, the complexity of the PCB board circuit design is reduced, the PCB board space is reduced, which is conducive to the miniaturization design of the PCB board.

[0041] Furthermore, the radio frequency chip 31 includes a first radio frequency port E and a second radio frequency port F. The first radio frequency port E is connected to the first antenna 11 through the first radio frequency feed line 51, and the second radio frequency port F is connected to the second antenna 12 through the second radio frequency feed line 52. The radio frequency chip 31 transmits and receives radio frequency signals through the first antenna 11 and the second antenna 12 to realize the function of transmitting and receiving radio frequency signals.

[0042] Furthermore, the present invention also provides a mobile terminal, which includes the radio frequency circuit described above. Since the radio frequency circuit has been described in detail above, it will not be repeated here.

[0043] In summary, the radio frequency circuit and mobile terminal provided by this invention include a radio frequency circuit comprising a first antenna, a second antenna, a radio frequency chip, a baseband chip, a first antenna tuner, and a second antenna tuner. The baseband chip includes a first port, which is connected to the first antenna tuner and the second antenna tuner respectively via a first control line. The radio frequency chip is connected to both the first and second antennas. The first antenna is connected to the first antenna tuner, and the second antenna is connected to the second antenna tuner. The baseband chip is used to output a first control signal to the first and second antenna tuners via the first port to adjust the impedance of the first and second antenna tuners. By multiplexing the control lines, this invention can effectively reduce the wiring of the control lines and save ports on the baseband chip.

[0044] It is understood that those skilled in the art can make equivalent substitutions or modifications to the technical solution and inventive concept of the present invention, and all such substitutions or modifications should fall within the protection scope of the appended claims.

Claims

1. A radio frequency circuit, characterized in that, The system includes a first antenna, a second antenna, an RF chip, a baseband chip, a first antenna tuner, and a second antenna tuner. The baseband chip includes a first port and a second port. The first port is connected to both the first and second antenna tuners via a first control line, and the second port is connected to both the first and second antenna tuners via a second control line. The RF chip is connected to both the first and second antennas. The first antenna is connected to the first antenna tuner, and the second antenna is connected to the second antenna tuner. The baseband chip is used to output a first control signal to the first antenna tuner and the second antenna tuner through the first port, and to output a second control signal to the first antenna tuner and the second antenna tuner through the second port, so that the first control signal and the second control signal jointly adjust the impedance of the first antenna tuner and the second antenna tuner; When the control signal of the first control line changes, both the first antenna tuner and the second antenna tuner will switch states.

2. The radio frequency circuit according to claim 1, characterized in that, Both the first port and the second port are GPIO ports.

3. The radio frequency circuit according to claim 1, characterized in that, The first antenna tuner includes four first impedance matching channels, and the first antenna tuner is used to turn on one of the four first impedance matching channels according to the first control signal and the second control signal.

4. The radio frequency circuit according to claim 3, characterized in that, The second antenna tuner includes four second impedance matching channels, and the second antenna tuner is used to turn on one of the four second impedance matching channels according to the first control signal and the second control signal.

5. The radio frequency circuit according to claim 1, characterized in that, The radio frequency chip includes a first radio frequency port and a second radio frequency port. The first radio frequency port is connected to the first antenna through a first radio frequency feed line, and the second radio frequency port is connected to the second antenna through a second radio frequency feed line.

6. A radio frequency circuit, characterized in that, The system includes a first antenna, a second antenna, an RF chip, a baseband chip, a first antenna tuner, and a second antenna tuner. The baseband chip includes a first port, a third port, and a fourth port. The first port is connected to both the first and second antenna tuners via a first control line. The third port is connected to the first antenna tuner via a third control line. The fourth port is connected to the second antenna tuner via a fourth control line. The RF chip is connected to both the first and second antennas. The first antenna is connected to the first antenna tuner, and the second antenna is connected to the second antenna tuner. The baseband chip is used to output a first control signal to the first antenna tuner and the second antenna tuner through the first port, output a third control signal to the first antenna tuner through the third port, and output a fourth control signal to the second antenna tuner through the fourth port, so that the first control signal and the third control signal jointly adjust the impedance of the first antenna tuner, and the first control signal and the fourth control signal jointly adjust the impedance of the second antenna tuner. When the control signal of the first control line changes, both the first antenna tuner and the second antenna tuner will switch states.

7. The radio frequency circuit according to claim 6, characterized in that, The first antenna tuner includes four first impedance matching channels, and the first antenna tuner is used to turn on one of the four first impedance matching channels according to the first control signal and the third control signal.

8. The radio frequency circuit according to claim 7, characterized in that, The second antenna tuner includes four second impedance matching channels, and the second antenna tuner is used to turn on one of the four second impedance matching channels according to the first control signal and the fourth control signal.

9. The radio frequency circuit according to claim 6, characterized in that, The radio frequency chip includes a first radio frequency port and a second radio frequency port. The first radio frequency port is connected to the first antenna through a first radio frequency feed line, and the second radio frequency port is connected to the second antenna through a second radio frequency feed line.

10. A mobile terminal, characterized in that, Includes the radio frequency circuit as described in any one of claims 1-9.

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