A radio frequency circuit that improves port utilization
By introducing transceiver modules and surface acoustic wave filters into the RF circuit, the problems of low port utilization and high insertion loss were solved, thereby improving port utilization and reducing costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SICHUAN COOLBY COMM EQUIP CO LTD
- Filing Date
- 2025-06-16
- Publication Date
- 2026-06-05
AI Technical Summary
The low port utilization of existing RF circuits leads to increased costs and a larger circuit board footprint, and frequent internal switching results in significant insertion loss.
The radio frequency circuit is integrated on a single circuit board. The frequency band is switched by the transceiver module, which includes a double-pole double-throw switch and a single-pole double-throw switch, reducing the number of ports used. The internal switching of the power amplifier is replaced by a double-pole double-throw switch. The surface acoustic wave filter is used to reduce the number of filters and wiring.
It improves port utilization, reduces costs, reduces circuit board footprint, and solves the insertion loss problem caused by internal switch switching, making the layout more flexible.
Smart Images
Figure CN224329462U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of electronic technology, and in particular to a radio frequency circuit that improves port utilization. Background Technology
[0002] The design of existing radio frequency circuits is always constrained by layout space, device ports, and cost, such as Figure 1 As shown, taking Band 40 (Band 40 band) and Band 41 (Band 41 band) as examples, a B40 filter A (used in Band 40 band) and a B41 filter B (used in Band 41 band) are set for the power amplifier (PA) and low-noise amplifier (LNA), respectively. The four filters are connected to the antenna ANT via a single-pole four-throw (SP4T) switch to switch the transmit and receive paths. One set of B40 and B41 filters occupies two ports of the power amplifier, connecting to the internal switch of the power amplifier, resulting in significant insertion loss due to the internal switch switching the frequency band. Another set of B40 and B41 filters occupies two ports of the low-noise amplifier. Due to the circuit layout, the distance between the power amplifier and the low-noise amplifier cannot be too far (a greater distance would further increase insertion loss), and the filters also need to be connected to the SP4T switch, leading to increased wiring. Each device is connected by a separate trace, resulting in eight transmission lines from the four filters and numerous ports for docking with the corresponding devices. The power amplifier and low-noise amplifier each occupy two ports, significantly reducing port utilization. Two sets of B40 and B41 filters are required, increasing costs. The single-pole four-throw switch and filters are also relatively large, increasing the area occupied by the circuit board.
[0003] Therefore, existing technologies still need to be improved and enhanced. Utility Model Content
[0004] In view of the shortcomings of the prior art, the purpose of this utility model is to provide a radio frequency circuit that improves port utilization, so as to solve the problem of low port utilization in existing radio frequency circuits.
[0005] To achieve the above objectives, the present invention adopts the following technical solution:
[0006] A radio frequency (RF) circuit for improving port utilization is integrated on a circuit board, including a power amplifier, a low-noise amplifier, an RF chip, and an antenna. The RF circuit also includes a transceiver module, wherein a first transmission terminal of the transceiver module is connected to the power amplifier, a second transmission terminal of the transceiver module is connected to the low-noise amplifier, a third transmission terminal of the transceiver module is connected to the antenna, and a control terminal of the transceiver module is connected to the RF chip.
[0007] The radio frequency chip controls the switching of preset frequency band transmission paths within the transceiver module; the transceiver module selects the corresponding frequency band according to the switching operation, and transmits and receives radio frequency signals between the power amplifier and the antenna, and between the low noise amplifier and the antenna.
[0008] In the radio frequency circuit for improving port utilization, the transceiver module includes a double-pole double-throw switch, a single-pole double-throw switch, a first filter, and a second filter.
[0009] The RF1 terminal of the double-pole double-throw switch is connected to the output terminal of the power amplifier, the RF2 terminal of the double-pole double-throw switch is connected to the input terminal of the low-noise amplifier, the S1 terminal of the double-pole double-throw switch is connected to the GPIO1 pin of the RF chip, the RF3 terminal of the double-pole double-throw switch is connected to the RF2 terminal of the single-pole double-throw switch through the second filter, the RF4 terminal of the double-pole double-throw switch is connected to the RF1 terminal of the single-pole double-throw switch through the first filter, the C terminal of the single-pole double-throw switch is connected to the antenna, and the S2 terminal of the single-pole double-throw switch is connected to the GPIO2 pin of the RF chip.
[0010] In the radio frequency circuit for improving port utilization, the first filter is a surface acoustic wave filter in the Band 41 band, and the second filter is a surface acoustic wave filter in the Band 40 band.
[0011] In the radio frequency circuit for improving port utilization, the first filter is a surface acoustic wave filter in the Band 39 band, and the second filter is a surface acoustic wave filter in the Band 34 band.
[0012] The radio frequency circuit for improving port utilization includes a first antenna and a second antenna. The transceiver module includes a first double-pole double-throw switch, a second double-pole double-throw switch, a first filter, and a second filter. The RF1 terminal of the first double-pole double-throw switch is connected to the output terminal of the power amplifier, the RF2 terminal of the first double-pole double-throw switch is connected to the input terminal of the low-noise amplifier, the S1 terminal of the first double-pole double-throw switch is connected to the GPIO1 pin of the radio frequency chip, the RF3 terminal of the first double-pole double-throw switch is connected to the RF2 terminal of the second double-pole double-throw switch through the second filter, the RF4 terminal of the first double-pole double-throw switch is connected to the RF1 terminal of the second double-pole double-throw switch through the first filter, the RF4 terminal of the second double-pole double-throw switch is connected to the first antenna, the RF3 terminal of the second double-pole double-throw switch is connected to the second antenna, and the S1 terminal of the second double-pole double-throw switch is connected to the GPIO2 pin of the radio frequency chip.
[0013] Compared to existing technologies, the RF circuit for improving port utilization provided by this utility model is integrated on a single circuit board, including a power amplifier, a low-noise amplifier, an RF chip, an antenna, and a transceiver module. The first transmission terminal of the transceiver module is connected to the power amplifier, the second transmission terminal is connected to the low-noise amplifier, the third transmission terminal is connected to the antenna, and the control terminal is connected to the RF chip. The RF chip controls the switching of preset frequency band transmission paths within the transceiver module. The transceiver module selects the corresponding frequency band according to the switching operation, and transmits and receives RF signals between the power amplifier and the antenna, and between the low-noise amplifier and the antenna. Through this transceiver module, the power amplifier and the low-noise amplifier each only need to provide one port for signal transmission, reducing the number of ports used and improving port utilization. It eliminates the need for an internal switch in the power amplifier to switch frequency bands, solving the problem of high insertion loss caused by frequent switching during transmission and reception. Attached Figure Description
[0014] Figure 1 This is a circuit diagram of an existing radio frequency circuit.
[0015] Figure 2 This is a circuit diagram of the radio frequency circuit that improves port utilization provided by this utility model. Detailed Implementation
[0016] This invention provides a radio frequency circuit for improving port utilization. To make the objectives, technical solutions, and advantages of this invention clearer and more explicit, the following detailed description, with reference to the accompanying drawings and embodiments, further illustrates the invention. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of the invention.
[0017] Please see Figure 2 This utility model provides an integrated radio frequency (RF) circuit on a circuit board that improves port utilization. It includes a power amplifier (PA) 10, a low-noise amplifier (LNA) 20, an RF IC 30, an antenna ANT, and an improved transceiver module 40 as described in this embodiment. The first transmission terminal 1 of the transceiver module 40 is connected to the power amplifier 10, the second transmission terminal 2 is connected to the low-noise amplifier 20, the third transmission terminal 3 is connected to the antenna ANT, and the control terminal 4 is connected to the RF IC 30. The RF IC 30 controls the switching of preset frequency band transmission paths within the transceiver module 40. The transceiver module 40 selects the corresponding frequency band according to the switching operation, and transmits and receives RF signals between the power amplifier 10 and the antenna, and between the low-noise amplifier 20 and the antenna.
[0018] Through the connection of the transceiver module 40, the power amplifier (PA) 10 and the low-noise amplifier (LNA) 20 only need to provide one port each to transmit signals, reducing the number of ports used and improving port utilization. It also eliminates the need for internal switches in the power amplifier to switch frequency bands, solving the problem of high insertion loss caused by frequent switching during transmission and reception. It should be understood that the power amplifier (PA) 10, low-noise amplifier (LNA) 20, RFIC chip (RFIC) 30, and antenna ANT are existing technologies; this embodiment only changes the connection method of their port pins, without altering their internal circuit structure. This transceiver module 40 is suitable for various electronic devices with RF circuitry.
[0019] In this embodiment, the transceiver module 40 includes a double-pole double-throw (DPDT) switch, a single-pole double-throw (SP2T) switch, a first filter SAW1, and a second filter S2. The RF1 terminal (first transmission terminal, i.e., the first transmission terminal 1 of the transceiver module 40) of the DPDT switch is connected to the output terminal (power output port) of the power amplifier 10, the RF2 terminal (second transmission terminal, i.e., the second transmission terminal 2 of the transceiver module 40) of the DPDT switch is connected to the input terminal of the low-noise amplifier 20, and the S1 terminal (control terminal, i.e., the control terminal 4 of the transceiver module 40) of the DPDT switch is connected to the input terminal of the low-noise amplifier 20. Connect the GPIO1 pin (or MIPI pin) of the RF chip 30. The RF3 pin (third transmission pin) of the double-pole double-throw switch DPDT is connected to the RF2 pin (other transmission pin) of the single-pole double-throw switch SP2T through the second filter SAW2. The RF4 pin (fourth transmission pin) of the double-pole double-throw switch DPDT is connected to the RF1 pin (one transmission pin) of the single-pole double-throw switch SP2T through the first filter SAW1. The C pin (common pin) of the single-pole double-throw switch SP2T is connected to the antenna ANT. The S2 pin (control pin) of the single-pole double-throw switch SP2T is connected to the GPIO2 pin of the RF chip 30.
[0020] The first filter SAW1 can be a surface acoustic wave (SAW) filter in the Band 41 frequency band, and the second filter S2 can be a SAW filter in the Band 40 frequency band. The applicable frequency bands of the two filters can be set according to requirements, for example, the Band 41 frequency band can be replaced with the Band 39 frequency band, and the Band 40 frequency band can be replaced with the Band 34 frequency band. The default connection state of the double-pole double-throw (DPDT) switch is that RF1 is connected to RF4 and RF2 is connected to RF3. At this time, the first filter SAW1 is connected to the power amplifier 10, and the second filter SAW2 is connected to the low-noise amplifier. The RF chip 30 outputs a high-level (the level can be adjusted according to requirements) control signal to the S1 terminal of the DPDT, and the internal connection of the DPDT switch is switched to RF1 connected to RF3 and RF2 connected to RF4. At this time, the first filter SAW1 is connected to the low-noise amplifier, and the second filter SAW2 is connected to the power amplifier 10.
[0021] The connection and switching between the two filters is achieved by a double-pole double-throw (DPDT) switch, instead of the internal switch of the power amplifier. The insertion loss of the DPDT is lower than that of the internal switch, thus avoiding the problem of high insertion loss in the power amplifier's internal switch. Simultaneously, the transceiver module 40 only needs two filters, saving both cost and board space compared to the existing four filters. The two amplifiers only need one necessary port for signal transmission, and the connection between the single-pole double-throw (SP2T) switch and the filter is also reduced to two ports. The overall number of ports used is significantly reduced by four compared to the existing method, greatly improving port utilization. In terms of layout and routing, the reduced number of connection lines between ports, fewer filters, and shorter traces allow for more flexible layout, free from the constraints of PA position; the DPDT can be placed close to the filter.
[0022] Please continue reading. Figure 2 Taking Band 40 and Band 41 as examples, the working principle of the radio frequency circuit is as follows:
[0023] When B41 is selected for transmission, the RF chip 30 outputs a low-level first control signal to the S1 terminal of the DPDT, and a low-level second control signal to the S2 terminal of the SP2T. At this time, the RF1 terminal of the DPDT is connected to the RF4 terminal. The transmitted signal is amplified by the power amplifier 10 and then transmitted to the SAW1 filter via the DPDT. At this time, the RF1 terminal of the single-pole double-throw switch SP2T is connected to the C terminal, and the filtered transmitted signal is transmitted to the antenna for transmission through the SP2T.
[0024] When B40 is selected for transmission, the RF chip 30 outputs a high-level first control signal to the S1 terminal of the DPDT, and a high-level second control signal to the S2 terminal of the SP2T. At this time, the RF1 terminal of the DPDT is connected to the RF3 terminal. The transmitted signal is amplified by the power amplifier 10 and then transmitted to the SAW2 filter via the DPDT. At this time, the RF2 terminal of the single-pole double-throw switch SP2T is connected to the C terminal, and the filtered transmitted signal is transmitted to the antenna for transmission via the SP2T.
[0025] When B41 is selected for reception, RF chip 30 outputs a low-level second control signal, controlling the RF1 terminal of the single-pole double-throw switch SP2T to connect to the C terminal. The received signal received by the antenna is transmitted to the SAW1 filter through SP2T. RF chip 30 then outputs a high-level first control signal to the S terminal of the DPDT. At this time, the RF4 terminal of the DPDT is connected to the RF2 terminal, and the received signal filtered by SAW1 is transmitted to the low-noise amplifier 20 through the DPDT.
[0026] When B40 is selected for reception, RF chip 30 outputs a high-level second control signal, controlling the RF2 terminal of the single-pole double-throw switch SP2T to connect to terminal C. The received signal received by the antenna is transmitted to the SAW2 filter via SP2T. RF chip 30 then outputs a low-level first control signal to the S1 terminal of the DPDT. At this time, RF3 terminal is connected to RF2 terminal, and the received signal filtered by SAW2 is transmitted to the low-noise amplifier 20 via the DPDT.
[0027] In practical implementation, the number of antennas is not limited to one. For example, two or three different types of antennas can be used. In this case, the single-pole double-throw switch SP2T can be replaced with a double-pole double-throw switch or a three-to-one analog switch. There is no limitation here. When two antennas are set, the transceiver module includes a first double-pole double-throw switch, a second double-pole double-throw switch, a first filter, and a second filter. The RF1 terminal of the first double-pole double-throw switch is connected to the output terminal of the power amplifier, the RF2 terminal of the first double-pole double-throw switch is connected to the input terminal of the low-noise amplifier, the S1 terminal of the first double-pole double-throw switch is connected to the GPIO1 pin of the RF chip, the RF3 terminal of the first double-pole double-throw switch is connected to the RF2 terminal of the second double-pole double-throw switch through the second filter, the RF4 terminal of the first double-pole double-throw switch is connected to the RF1 terminal of the second double-pole double-throw switch through the first filter, the RF4 terminal of the second double-pole double-throw switch is connected to the first antenna, the RF3 terminal of the second double-pole double-throw switch is connected to the second antenna, and the S1 terminal of the second double-pole double-throw switch is connected to the GPIO2 pin of the RF chip.
[0028] In summary, the RF circuit of this invention, which improves port utilization, requires only two filters switched by a double-pole double-throw switch. Compared to existing power amplifiers that rely on internal switches, this solves the problem of high insertion loss associated with internal switches. The overall number of components used is less than existing designs, reducing costs, allowing for more flexible layout, and reducing the number of connected ports, thus significantly improving port utilization.
[0029] It should be understood that the application of this utility model is not limited to the examples above. Those skilled in the art can make improvements or modifications based on the above description, and all such improvements and modifications should fall within the protection scope of the appended claims.
Claims
1. A radio frequency circuit for improving port utilization, integrated on a circuit board, comprising a power amplifier, a low-noise amplifier, a radio frequency chip, and an antenna, characterized in that, The radio frequency circuit also includes a transceiver module, wherein the first transmission terminal of the transceiver module is connected to a power amplifier, the second transmission terminal of the transceiver module is connected to a low noise amplifier, the third transmission terminal of the transceiver module is connected to an antenna, and the control terminal of the transceiver module is connected to a radio frequency chip. The radio frequency chip controls the switching of preset frequency band transmission paths within the transceiver module; the transceiver module selects the corresponding frequency band according to the switching operation, and transmits and receives radio frequency signals between the power amplifier and the antenna, and between the low noise amplifier and the antenna.
2. The radio frequency circuit for improving port utilization according to claim 1, characterized in that, The transceiver module includes a double-pole double-throw switch, a single-pole double-throw switch, a first filter, and a second filter; The RF1 terminal of the double-pole double-throw switch is connected to the output terminal of the power amplifier, the RF2 terminal of the double-pole double-throw switch is connected to the input terminal of the low-noise amplifier, the S1 terminal of the double-pole double-throw switch is connected to the GPIO1 pin of the RF chip, the RF3 terminal of the double-pole double-throw switch is connected to the RF2 terminal of the single-pole double-throw switch through the second filter, the RF4 terminal of the double-pole double-throw switch is connected to the RF1 terminal of the single-pole double-throw switch through the first filter, the C terminal of the single-pole double-throw switch is connected to the antenna, and the S2 terminal of the single-pole double-throw switch is connected to the GPIO2 pin of the RF chip.
3. The radio frequency circuit for improving port utilization according to claim 2, characterized in that, The first filter is a surface acoustic wave filter in the Band 41 frequency band, and the second filter is a surface acoustic wave filter in the Band 40 frequency band.
4. The radio frequency circuit for improving port utilization according to claim 2, characterized in that, The first filter is a surface acoustic wave filter in the Band 39 frequency band, and the second filter is a surface acoustic wave filter in the Band 34 frequency band.
5. The radio frequency circuit for improving port utilization according to claim 1, characterized in that, The transceiver module includes a first antenna and a second antenna, and comprises a first double-pole double-throw switch, a second double-pole double-throw switch, a first filter, and a second filter. The RF1 terminal of the first double-pole double-throw switch is connected to the output terminal of a power amplifier, the RF2 terminal of the first double-pole double-throw switch is connected to the input terminal of a low-noise amplifier, the S1 terminal of the first double-pole double-throw switch is connected to the GPIO1 pin of an RF chip, the RF3 terminal of the first double-pole double-throw switch is connected to the RF2 terminal of the second double-pole double-throw switch via the second filter, the RF4 terminal of the first double-pole double-throw switch is connected to the RF1 terminal of the second double-pole double-throw switch via the first filter, the RF4 terminal of the second double-pole double-throw switch is connected to the first antenna, the RF3 terminal of the second double-pole double-throw switch is connected to the second antenna, and the S1 terminal of the second double-pole double-throw switch is connected to the GPIO2 pin of the RF chip.