Receiving and transmitting circuit of 5G signal monitor and communication equipment

Abstract

The utility model provides a receiving and transmitting circuit of a 5G signal monitor. The receiving and transmitting circuit comprises a receiving and transmitting port, a receiving link, a transmitting link, a switching module and a frequency conversion module, the receiving and transmitting port is coupled to the receiving link and the transmitting link through the switching module, and the receiving link and the transmitting link are coupled to the frequency conversion module. The frequency conversion module is used for receiving the radio frequency signal transmitted by the receiving link and performing down-conversion processing or performing up-conversion processing on an analog baseband signal and then transmitting the processed signal to the transmitting link; the receiving link comprises a low-noise amplifier, a low-noise bypass amplifier and a gain amplifier which are connected in sequence, and the low-noise amplifier is in coupling connection with the switching module; the transmitting link comprises a driving amplifier, a power amplifier and a harmonic filter which are connected in sequence; and the harmonic filter is coupled with the switching module. According to the scheme, a direct frequency conversion structure is adopted, and the scheme cost and the total power consumption of the transceiver are reduced.

Description

Technical Field

[0001] The utility model relates to the technical field of communication technology, and specifically to a transceiver circuit and communication equipment of a 5G signal monitor. Background Art

[0002] The 5G test system consists of three components: 5G frequency sweeping equipment, data analysis software, and cloud storage and applications. The RF transceiver is key to the development of the 5G frequency sweeping equipment, connecting external electromagnetic wave signals to the drive tester. After the antenna collects the RF signal from the external field, the receiver demodulates it, extracts the useful signal, and sends it to the baseband for processing. The large amount of collected drive test data, such as signal quality, signaling, and cell information, is used to assess network quality. The transmitter modulates the baseband data and transmits it as an RF signal.

[0003] With the rapid development of 5G technology, the higher-order modulation methods, hundreds of megabits of signal bandwidth, and Massive MIMO (Massive MIMO) technologies proposed by 5G networks have put forward more stringent design requirements for RF transceivers. Utility Model Content

[0004] In response to the shortcomings of the existing technology, the present invention proposes a transceiver circuit for a 5G signal monitor, which can ensure the radio frequency signal transceiver effect while making the structure more integrated and reducing production costs.

[0005] The technical solution of the present utility model is achieved as follows:

[0006] A transceiver circuit of a 5G signal monitor includes a transceiver port, a receiving link, a transmitting link, a switching module, and a frequency conversion module; the transceiver port is coupled to the receiving link and the transmitting link through the switching module, and the receiving link and the transmitting link are coupled to the frequency conversion module. The frequency conversion module is used to receive the radio frequency signal transmitted by the receiving link for down-conversion processing or to up-convert the analog baseband signal and then transmit it to the transmitting link.

[0007] A further technical solution of this embodiment is that the receiving chain includes a low-noise amplifier, a low-noise bypass amplifier and a gain amplifier connected in sequence, the low-noise amplifier is coupled to the switching module, and a bandpass filter is coupled between the low-noise amplifier, the low-noise bypass amplifier and the gain amplifier.

[0008] A further technical solution of this embodiment is that it further includes a digitally controlled attenuator, and the low-noise amplifier is coupled to the low-noise bypass amplifier through the digitally controlled attenuator.

[0009] A further technical solution of this embodiment is that the transmission chain includes a driver amplifier, a power amplifier and a harmonic filter connected in sequence, the harmonic filter is coupled to the switching module, and a bandpass filter is coupled between the driver amplifier, the power amplifier and the harmonic filter.

[0010] A further technical solution of this embodiment is that it further includes a radio frequency switch, which is coupled in front of the driving amplifier and is used to switch synchronously when the switching module is in operation.

[0011] A further technical solution of this embodiment is that it further includes a low insertion loss isolator, and the power amplifier is coupled to the harmonic filter through the low insertion loss isolator.

[0012] A further technical solution of this embodiment is that it also includes a feedback device, which includes a coupled coupler and an attenuator. The power amplifier is coupled to the harmonic filter through the coupler, and the feedback device is used to dynamically calibrate the transmission signal.

[0013] A further technical solution of this embodiment is that the frequency conversion module includes a down-conversion circuit and an up-conversion circuit; the down-conversion circuit includes an I mixer, a Q mixer, and an ADC converter, and the receiving link is coupled to the ADC converter through the I mixer and the Q mixer; the up-conversion circuit includes an I mixer, a Q mixer, and a DAC converter, and the transmitting link is coupled to the DAC converter through the I mixer and the Q mixer.

[0014] A further technical solution of this embodiment is that it further includes a plurality of I / Q low-pass filters, and the I / Q low-pass filters are coupled to the I mixer and the Q mixer respectively.

[0015] The second aspect of this embodiment proposes a communication device, including a transceiver antenna, a transceiver circuit of the 5G signal monitor as described above, and a transceiver chip connected in sequence.

[0016] Compared with the prior art, the utility model has the following advantages:

[0017] The utility model adopts a direct frequency conversion structure, which directly converts the useful signal to near DC after only one frequency conversion. By simplifying the intermediate frequency link design, the solution cost and off-chip area are effectively saved. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the implementation methods or the description of the prior art. Obviously, the drawings described below are only some implementation methods of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0019] Figure 1 It is a structural block diagram of the 5G test system in the background technology;

[0020] Figure 2 This is a structural block diagram of the transceiver circuit of a 5G signal monitor in the present utility model;

[0021] Figure 3 This is a structural diagram of the receiving link in the present utility model;

[0022] Figure 4 This is a structural diagram of the transmission link in the present utility model.

[0023] Figure identification: 1-receiving link; 2-transmitting link; 3-switching module; 4-frequency conversion module. DETAILED DESCRIPTION

[0024] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0025] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are intended solely to facilitate the description of this utility model and simplify the description. They do not indicate or imply that the devices or components referred to must have a specific orientation, be constructed, or operate in a specific orientation. Therefore, they should not be construed as limitations on this utility model. Furthermore, the terms "first," "second," "third," and "fourth," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0026] In the description of this utility model, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; mechanical connections, electrical connections; direct connections, indirect connections through an intermediate medium, and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in this utility model based on the specific circumstances.

[0027] like Figure 1 As shown, Figure 1 The system architecture of a 5G test system is shown in Figure 1. The frequency sweeping device primarily integrates a baseband signal processor and transceiver circuits, enabling the frequency sweeping device to receive and transmit RF signals. The transceiver circuits can exchange signals with the baseband signal processor, which typically includes a central processing unit (CPU), a media access control (MAC) layer, and a physical layer (PHY). The CPU, MAC, and PHY can be implemented through corresponding protocol layer processing modules according to the functions of each protocol layer in the communication device. For example, the PHY layer can implement the functions of the PHY layer in protocols such as 802.11a, 802.11b, 802.11g, 802.11n, and 802.11ac, while the MAC layer can implement the functions of the MAC layer in protocols such as 802.11a, 802.11b, 802.11g, 802.11n, and 802.11ac.

[0028] Due to the higher-order modulation methods, hundreds of megabits of signal bandwidth, and massive MIMO (Massive MIMO) technologies proposed by 5G, the dynamic range and power loss of existing 5G scanning equipment are difficult to meet the index requirements.

[0029] Based on this, Figure 2As shown, the embodiment of the present invention discloses a transceiver circuit of a 5G signal monitor, including a transceiver port, a receiving link 1, a transmitting link 2, a switching module 3, and a frequency conversion module 4; the transceiver port is coupled to the receiving link 1 and the transmitting link 2 through the switching module 3, and the receiving link 1 and the transmitting link 2 are coupled to the frequency conversion module 4, and the frequency conversion module 4 is used to receive the radio frequency signal transmitted by the receiving link for down-conversion processing or to perform up-conversion processing on the analog baseband signal and then transmit it to the transmitting link 2. The present application adopts a direct frequency conversion structure, and the phase-locked loop circuit enables the local oscillator signal to always be accurately aligned with the useful signal under high frequency conditions, so that the useful signal can be directly converted to near DC in one frequency conversion while skipping the intermediate frequency stage. At this time, the intermediate frequency signal is zero, and there is no problem of superheterodyne structure image interference, so there is no need to use high-quality IR filters and a large number of peripheral devices, thereby saving solution costs and off-chip area.

[0030] This embodiment utilizes a time division duplex (TDD) mode, where the transceiver circuit supports signal reception or transmission in only one frequency band at a time. When switching module 3 switches to the receive state, the RF signal enters receive chain 1 and is amplified by a low-noise amplifier and a dynamic gain amplifier. RF bandpass filters at various stages between chains filter out out-of-band interference signals. The demodulator then directly down-converts the signals to produce two analog baseband signals, I(t) and Q(t). These signals are then converted to digital signals by the ADC and sent to baseband processing. The signal processing process in transmit chain 2 is the opposite.

[0031] like Figure 3 As shown, in an embodiment of the present application, the receiving chain 1 includes a low-noise amplifier, a low-noise bypass amplifier, and a gain amplifier connected in sequence. The low-noise amplifier is coupled to the switching module 3, and a band-pass filter is coupled between the low-noise amplifier, the low-noise bypass amplifier, and the gain amplifier. Since the dynamic range of the existing transceiver chip cannot meet the index requirement of the receiving chain 1 for a dynamic range greater than 60dB, it is necessary to design a first-stage low-noise bypass amplifier to increase the dynamic range of the receiver while controlling the noise coefficient. The final-stage gain amplifier can ensure the small-signal power amplification capability of the receiving chain 1, so that it can reach the optimal input value of the back-end transceiver chip when receiving a minimum signal of -90dBm; the multi-stage band-pass filter set between the amplifiers is used to filter out out-of-band noise.

[0032] In one example, a digitally controlled attenuator is further included, through which the low-noise amplifier is coupled to the low-noise bypass amplifier. Because a single-stage bypass amplifier is insufficient to achieve 30dB gain control, a digitally controlled attenuator is also included to meet the 30dB adjustable range requirement of the receiving front end.

[0033] like Figure 4 As shown, in order to meet the requirement of a maximum transmission power of 20 dB, the transmission chain 2 adopts a two-stage amplification structure. The transmission chain 2 includes a driver amplifier, a power amplifier, and a harmonic filter connected in sequence. The harmonic filter is coupled to the switching module 3. A bandpass filter is coupled between the driver amplifier, the power amplifier, and the harmonic filter.

[0034] In this embodiment of the present application, a radio frequency switch is further included. The radio frequency switch is coupled to the front of the driver amplifier and is used to switch synchronously when the switching module 3 is activated. The radio frequency switch is different from the switching module 3 used for switching between transmission and reception between the two links. Its purpose is to protect the transmission link 2 when switching between the transmission and reception links.

[0035] In one example, a low insertion loss isolator is further included, through which the power amplifier is coupled to the harmonic filter. The low insertion loss isolator added after the final power amplifier can prevent the high-power signal echo from being transmitted and causing the power amplifier to burn out.

[0036] In one example, a feedback device is also included, and the feedback device includes a coupled coupler and an attenuator, and the power amplifier is coupled to the harmonic filter through the coupler, and the feedback device is used to dynamically calibrate the transmission signal. The feedback module composed of the coupler and the attenuator feeds back the transmission signal to the receiving observer of the transceiver chip to ensure the dynamic calibration of the transmission signal. A bandpass filter is also added to the post-amplifier stage in the transmission chain 2 to filter out out-of-band spurious signals, and the final filter is a harmonic filter for filtering out harmonics. The insertion loss values ​​of the isolator, coupler and harmonic filter are all low, which can reduce the power loss of the output signal of the final power amplifier.

[0037] In the embodiment of the present application, the frequency conversion module 4 includes a down-conversion circuit and an up-conversion circuit; the down-conversion circuit includes an I mixer, a Q mixer, and an ADC converter, and the receiving chain 1 is coupled to the ADC converter via the I mixer and the Q mixer; the up-conversion circuit includes an I mixer, a Q mixer, and a DAC converter, and the transmitting chain 2 is coupled to the DAC converter via the I mixer and the Q mixer. It can be understood that

[0038] In one example, several I / Q low-pass filters are further included, each coupled to the I mixer and the Q mixer. Due to the direct conversion structure, the intermediate frequency filter is eliminated, and the transceiver circuit relies on the back-end I / Q low-pass filters to achieve in-band suppression.

[0039] The present application also proposes a communication device, comprising a sequentially connected transceiver antenna, a transceiver circuit such as any of the 5G signal monitors described in the aforementioned embodiments, and a transceiver chip, wherein the transceiver antenna is coupled to the transceiver port, and the frequency conversion module 4 is coupled to the transceiver chip, which is used to process two analog baseband signals I(t) and Q(t) and send the analog baseband signals to the transmission link 2. In this embodiment, the transceiver chip is preferably an ADRV9009 chip.

[0040] In one embodiment, the digitally controlled attenuator and low-noise bypass amplifier in the receiving chain 1 are communicated with the transceiver chip, and the 30dB adjustable range indicator requirement of the receiving front end is met by digitally controlling the attenuator; the feedback module in the transmitting chain 2 is communicated with the transceiver chip, and the dynamic calibration of the transmitting signal is effectively ensured by synchronously feeding back the transmitting signal to the transceiver chip.

[0041] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A transceiver circuit of a 5G signal monitor, characterized in that: It includes a transceiver port, a receiving link, a transmitting link, a switching module, and a frequency conversion module; the transceiver port is coupled to the receiving link and the transmitting link through the switching module, and the receiving link and the transmitting link are coupled to the frequency conversion module. The frequency conversion module is used to receive the radio frequency signal transmitted by the receiving link for down-conversion processing or to up-convert the analog baseband signal and then transmit it to the transmitting link.

2. The transceiver circuit of the 5G signal monitor according to claim 1, wherein: The receiving chain includes a low-noise amplifier, a low-noise bypass amplifier and a gain amplifier connected in sequence. The low-noise amplifier is coupled to the switching module. A bandpass filter is coupled between the low-noise amplifier, the low-noise bypass amplifier and the gain amplifier.

3. The transceiver circuit of the 5G signal monitor according to claim 2, characterized in that: The invention also includes a digitally controlled attenuator, wherein the low noise amplifier is coupled to the low noise bypass amplifier through the digitally controlled attenuator.

4. The transceiver circuit of the 5G signal monitor according to claim 1, wherein: The transmission chain includes a driving amplifier, a power amplifier and a harmonic filter connected in sequence. The harmonic filter is coupled to the switching module. A bandpass filter is coupled between the driving amplifier, the power amplifier and the harmonic filter.

5. The transceiver circuit of the 5G signal monitor according to claim 4, characterized in that: It also includes a radio frequency switch, which is coupled in front of the driving amplifier and is used to switch synchronously when the switching module is in action.

6. The transceiver circuit of the 5G signal monitor according to claim 4, characterized in that: A low insertion loss isolator is also included, and the power amplifier is coupled to the harmonic filter through the low insertion loss isolator.

7. The transceiver circuit of the 5G signal monitor according to claim 4, characterized in that: It also includes a feedback device, which includes a coupled coupler and an attenuator. The power amplifier is coupled to the harmonic filter through the coupler. The feedback device is used to dynamically calibrate the transmission signal.

8. The transceiver circuit of the 5G signal monitor according to claim 1, characterized in that: The frequency conversion module includes a down-conversion circuit and an up-conversion circuit; the down-conversion circuit includes an I mixer, a Q mixer, and an ADC converter, and the receiving link is coupled to the ADC converter through the I mixer and the Q mixer; the up-conversion circuit includes an I mixer, a Q mixer, and a DAC converter, and the transmitting link is coupled to the DAC converter through the I mixer and the Q mixer.

9. The transceiver circuit of the 5G signal monitor according to claim 8, characterized in that: It also includes several I / Q low-pass filters, which are coupled to the I mixer and the Q mixer respectively.

10. A communication device, characterized in that: It includes a transceiver antenna connected in sequence, a transceiver circuit of the 5G signal monitor as described in any one of claims 1 to 9, and a transceiver chip.

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