A millimeter wave up and down conversion module

Abstract

The present application discloses a millimeter wave up-down conversion module, including an intermediate frequency transceiver conversion switch and an RF transceiver conversion switch, and there are two links between the two switches - an up-conversion link and a down-conversion link. The up-conversion link includes an intermediate frequency amplifier, a hybrid coupler, and an orthogonal up-converter in sequence. The down-conversion link includes a down-converter. There is also a local oscillator circuit that provides a local oscillator signal to the orthogonal up-converter and the down-converter. There is also an RF balun transformer connected to the RF transceiver conversion switch. The millimeter wave up-down conversion module has two working modes - a transmitting mode and a receiving mode. In the transmitting mode, the signal goes to the up-conversion link, and in the receiving mode, the signal goes to the down-conversion link. The present application enables the up-down conversion module to have a good image suppression ratio, low local oscillator leakage, broadband matching, small area and low design complexity.

Description

Technical Field

[0001] The present application relates to a wireless communication technology, and in particular to an up-down conversion module in a millimeter wave radio frequency transceiver. Background Art

[0002] The up-conversion and down-conversion modules in the RF transceiver include an up-converter and a down-converter. The up-converter is used to convert the low-frequency or intermediate-frequency signal to a high-frequency signal, and then radiate it through the subsequent amplification circuit; the down-converter is used to convert the high-frequency signal to a low-frequency or intermediate-frequency signal, and then process the low-frequency or intermediate-frequency signal through the baseband module.

[0003] With the development of wireless communication technology, the millimeter wave (mmWave) field has a larger allocated bandwidth because it works at a higher frequency. According to Shannon's theorem, millimeter wave systems are very attractive for improving the bandwidth, speed and other performance of circuits, and are often used in 5G communication systems. In millimeter wave systems, passive devices such as inductors and transformers are used extensively. In order to increase the integration, it is necessary to reduce the chip area and thus reduce costs. In terms of performance, millimeter wave systems focus on indicators such as linearity, input-output matching, gain and noise. The current technical difficulties are mainly image suppression and local oscillator leakage in the transmission mode. Therefore, designing a high-performance up and down conversion module is of great practical significance.

[0004] See also Figure 1 This is a system block diagram of a traditional millimeter-wave RF transceiver. The up-down conversion module is located between the intermediate frequency chip and the RF front-end chip to realize the up-conversion and down-conversion functions. At present, the common up-down conversion modules mainly have the following structures. Literature 1 adopts a direct up-down conversion structure, and the local oscillator signal is generated by an orthogonal voltage-controlled oscillator; for the up-converter, a digital-to-analog converter is used to calibrate the local oscillator leakage; and for the down-converter, an inductor is used at the output of the transconductance stage; overall, the area is large, the power consumption of the local oscillator link is large, and a calibration module is required to achieve better image suppression and local oscillator leakage suppression, and the comprehensive design is difficult. Literature 2 uses a passive structure converter with negative gain. In order to suppress the image frequency, a two-stage passive notch filter is used. Due to the influence of the inductor Q value, the loss is large, the suppression bandwidth is narrow, and the area is large. Literature 3 requires an off-chip filter to achieve image suppression, which is not conducive to high integration.

[0005] Reference 1: A 28-GHz CMOS Direct Conversion Transceiver With Packaged 2×4 Antenna Array for 5G Cellular System, published in IEEE Journal of Solid-State Circuits, Vol. 53, No. 5, April 23, 2018, by Hong-Teuk Kim et al.

[0006] Reference 2: A 28-GHz CMOS Phased-Array Transceiver Based on LO Phase-Shifting Architecture With Gain Invariant Phase Tuning for 5G New Radio, published in IEEE Journal of Solid-State Circuits, Vol. 54, No. 5, March 7, 2019, by Jiang Pang et al.

[0007] Document 3: "A High-Linearity, 24–30 GHz RF, Beamforming and Frequency-Conversion IC for Scalable 5G Phased Arrays", published at the 2021 IEEE Radio Frequency Integrated Circuits Symposium (RFIC) conference from June 7 to 9, 2021, written by Arun Paidimarri et al. Summary of the invention

[0008] The technical problem to be solved by the present application is how to make the up-down conversion module have high image suppression, high local oscillator leakage suppression, broadband matching, a certain dynamic range, and no need for calibration circuit, so as to be suitable for RF transceivers in the millimeter wave frequency band.

[0009] In order to solve the above technical problems, the present application proposes a millimeter wave up-down conversion module, including an intermediate frequency transceiver conversion switch and an RF transceiver conversion switch, and there are two links between the two switches - an up-conversion link and a down-conversion link. The up-conversion link includes an intermediate frequency amplifier, a hybrid coupler, and an orthogonal up-converter in sequence. The down-conversion link includes a down-converter. There is also a local oscillator circuit that provides a local oscillator signal to the orthogonal up-converter and the down-converter. There is also an RF balun transformer connected to the RF transceiver conversion switch. The millimeter wave up-down conversion module has two working modes - a transmitting mode and a receiving mode.

[0010] In the transmit mode, the IF transceiver switch sends the IF signal input from the IF port to the up-conversion link. The IF input signal is first converted from a single-ended IF signal to a differential IF signal and amplified by the IF amplifier. The amplified differential IF signal is then converted to an orthogonal IF signal by the hybrid coupler and provided to the orthogonal up-converter. The local oscillator circuit converts the single-ended local oscillator signal input from the local oscillator port into an orthogonal local oscillator signal and provides it to the orthogonal up-converter. The orthogonal up-converter mixes the orthogonal IF signal and the orthogonal local oscillator signal to obtain the RF signal and then outputs it differentially. The RF transceiver switch outputs the differential RF signal output by the orthogonal up-converter to the RF balun transformer 2. The RF balun transformer 2 converts the differential RF signal from the RF transceiver switch into a single-ended RF signal and outputs it to the antenna at the RF port.

[0011] In the receiving mode, the RF balun transformer 2 converts the single-ended RF signal received from the antenna at the RF port into a differential RF signal. The RF transceiver conversion switch sends the differential RF signal from the RF balun transformer 2 to the down-conversion link, specifically to the down-converter. The local oscillator circuit converts the single-ended local oscillator signal input at the local oscillator port into a differential local oscillator signal and provides it to the down-converter. The down-converter mixes the differential RF signal and the differential local oscillator signal to obtain a differential intermediate frequency signal, which is then converted into a single-ended intermediate frequency signal. The intermediate frequency transceiver conversion switch outputs the single-ended intermediate frequency signal output by the down-converter at the intermediate frequency port.

[0012] Furthermore, the intermediate frequency transceiver conversion switch consists of switch one and switch two; in the transmitting mode, switch one is turned on and switch two is turned off, and the single-ended intermediate frequency signal input by the intermediate frequency port is sent to the intermediate frequency amplifier in the up-conversion link via switch one; in the receiving mode, switch two is turned on and switch one is turned off, and the single-ended intermediate frequency signal output by the down-converter in the down-conversion link is output to the intermediate frequency port via switch two.

[0013] Furthermore, the intermediate frequency amplifier is composed of a transformer 1 and an intermediate frequency variable gain amplifier in cascade; the transformer 1 is used to realize the conversion from a single-ended intermediate frequency signal to a differential intermediate frequency signal, and the intermediate frequency variable gain amplifier is used to amplify the differential intermediate frequency signal.

[0014] Furthermore, the hybrid coupler has two input terminals, two isolation terminals and four output terminals; the two input terminals receive differential intermediate frequency signals output by the intermediate frequency amplifier; the two isolation terminals are connected to the two ends of a resistor representing a load at the isolation terminal; the hybrid coupler converts the two differential intermediate frequency signals into four orthogonal intermediate frequency signals and outputs them through four output terminals, and the four output terminals are respectively connected to four DC blocking capacitors to remove DC components in the four orthogonal intermediate frequency signals.

[0015] Furthermore, the orthogonal up-converter receives four orthogonal intermediate frequency signals and also receives four orthogonal local oscillator signals from a local oscillator circuit. The orthogonal intermediate frequency signals and the orthogonal local oscillator signals are mixed by the orthogonal up-converter to output two differential radio frequency signals.

[0016] Optionally, two output ends of the orthogonal up-converter are connected to a RF balun transformer 1; a primary coil of the RF balun transformer 1 is connected in parallel with a capacitor array, and the capacitor array is adjusted to cover different frequency bands.

[0017] Furthermore, the local oscillator circuit includes transformer 2, a local oscillator input buffer, switch 3 and switch 4, a down-conversion link buffer, an orthogonal all-pass filter, and an up-conversion link buffer.

[0018] In the transmitting mode, the single-ended local oscillator signal inputted by the local oscillator port is first converted into a differential local oscillator signal by transformer 2, and the differential local oscillator signal is then amplified by the local oscillator input buffer and sent to switch 3 and switch 4; switch 3 is turned on, switch 4 is turned off, and the differential local oscillator signal is transmitted to the orthogonal all-pass filter via switch 3; the orthogonal all-pass filter converts the two-way differential local oscillator signal into four-way orthogonal local oscillator signal, which is amplified by the up-conversion link buffer and outputted to the orthogonal up-converter.

[0019] In the receiving mode, the single-ended local oscillator signal input to the local oscillator port is first converted into a differential local oscillator signal by transformer 2, and the differential local oscillator signal is then amplified by the local oscillator input buffer and sent to switch 3 and switch 4; switch 4 is turned on, switch 3 is turned off, and the differential local oscillator signal is transmitted to the down-conversion link buffer via switch 4; the down-conversion link buffer amplifies the two differential local oscillator signals and outputs them to the down-converter.

[0020] Furthermore, the RF transceiver conversion switch consists of switch five and switch six; in the transmitting mode, switch five is turned on and switch six is ​​turned off, and the differential RF signal output by the orthogonal up-converter is transmitted to the RF balun transformer two after passing through switch five; in the receiving mode, switch six is ​​turned on and switch five is turned off, and the differential RF signal output by the RF balun transformer two is sent to the down-converter via switch six.

[0021] Furthermore, the RF balun transformer 2 is used to realize the conversion between differential RF signals and single-ended RF signals; in the transmitting mode, the RF balun transformer 2 converts the differential RF signal output by the RF transceiver conversion switch into a single-ended RF signal and sends it to the RF port output; in the receiving mode, the RF balun transformer 2 converts the single-ended RF signal input by the RF port into a differential RF signal and sends it to the RF transceiver conversion switch.

[0022] Furthermore, the output end of the down-converter is also connected to transformer three; the down-converter is used to down-convert the differential RF signal output by the RF transceiver conversion switch into a differential intermediate frequency signal based on the differential local oscillator signal; transformer three is used to convert the differential intermediate frequency signal into a single-ended intermediate frequency signal, and then send it to the intermediate frequency transceiver conversion switch.

[0023] Preferably, the transformer 1, transformer 2, transformer 3, RF balun transformer 1, and RF balun transformer 2 are all low-coupling transformers for achieving broadband matching.

[0024] Preferably, the switch one, switch two, switch three, switch four, switch five and switch six are switches with low insertion loss and high isolation.

[0025] The technical effect achieved by the present application is to enable the up-down conversion module to have a good image suppression ratio, low local oscillator leakage, broadband matching, small area and low design complexity. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 The present invention is a schematic diagram of the structure of an up-down conversion module in an existing millimeter wave radio frequency transceiver.

[0027] Figure 2 It is a schematic diagram of the overall structure of the millimeter wave up and down conversion module proposed in this application.

[0028] Figure 3 The diagram is a schematic structural diagram of an embodiment of an intermediate frequency transceiver conversion switch.

[0029] Figure 4 It is a schematic structural diagram of an embodiment of an intermediate frequency amplifier.

[0030] Figure 5 It is a schematic diagram of the structure of an embodiment of a hybrid coupler and an orthogonal up-converter.

[0031] Figure 6 It is a structural diagram of an embodiment of a local oscillator circuit.

[0032] Figure 7 It is a structural schematic diagram of an embodiment of a radio frequency transceiver conversion switch and a radio frequency balun transformer.

[0033] Figure 81 is a schematic structural diagram of an embodiment of a down converter.

[0034] Explanation of reference numerals in the figure: IF is the intermediate frequency port, LO is the local oscillator port, RF is the radio frequency port, T1 and T2 are both radio frequency balun transformers, sw1 to sw6 are switches, Tr1 to Tr3 are transformers, IF VGA is an intermediate frequency variable gain amplifier, R ISO is a resistor, C1 to C4 are DC blocking capacitors, C arr is a variable capacitor array, VDD is the power supply voltage, B1 is the local oscillator input buffer, B2 is the down-conversion link buffer, B3 and B4 are both up-conversion link buffers, C p1 and C p2 All are capacitors. DETAILED DESCRIPTION

[0035] See also Figure 2 The millimeter wave up-down conversion module proposed in this application includes an intermediate frequency transceiver conversion switch and an RF transceiver conversion switch. There are two links between the two switches: an up-conversion link and a down-conversion link. The up-conversion link includes an intermediate frequency amplifier, a hybrid coupler, and an orthogonal up-converter. The down-conversion link mainly includes a down-converter (only the main components are listed here, consisting of Figure 8 It can be seen that the down-conversion link also has transformer 3 Tr3). There is also a local oscillator circuit that provides local oscillator signals to the orthogonal up-converter and down-converter. There is also a RF balun (balun, Balanced to Unbalanced, balanced to unbalanced) transformer 2 T2 connected to the RF transceiver switch and between the RF transceiver switch and the antenna (not shown).

[0036] Figure 2 The millimeter wave up and down conversion module shown has two working modes: transmission mode and reception mode.

[0037] In the transmit mode, the IF transceiver conversion switch sends the IF signal input from the IF port IF to the up-conversion link. The IF input signal is first converted from a single-ended IF signal to a differential IF signal and amplified by the IF amplifier. The amplified differential IF signal is then converted to an orthogonal IF signal by a hybrid coupler and provided to the orthogonal up-converter. The local oscillator circuit converts the single-ended local oscillator signal input from the local oscillator port LO into an orthogonal local oscillator signal and provides it to the orthogonal up-converter. The orthogonal up-converter mixes (specifically up-converts) the orthogonal IF signal and the orthogonal local oscillator signal to obtain the RF signal and then outputs it differentially. The RF transceiver conversion switch outputs the differential RF signal output by the orthogonal up-converter to the RF balun transformer 2 T2. The RF balun transformer 2 T2 converts the differential RF signal from the RF transceiver conversion switch into a single-ended RF signal and outputs it at the RF port RF, for example, outputting it to Figure 1 The RF front-end chip in the .

[0038] In the receiving mode, the RF balun transformer 2 T2 converts the single-ended RF signal received by the RF port RF into a differential RF signal. The RF transceiver conversion switch sends the differential RF signal from the RF balun transformer 2 T2 to the down-conversion link, specifically to the down-converter. The local oscillator circuit converts the single-ended local oscillator signal input by the local oscillator port LO into a differential local oscillator signal and provides it to the down-converter. The down-converter mixes the differential RF signal and the differential local oscillator signal (specifically down-converts) to obtain a differential intermediate frequency signal, which is then converted into a single-ended intermediate frequency signal. The intermediate frequency transceiver conversion switch outputs the single-ended intermediate frequency signal output by the down-converter at the intermediate frequency port IF.

[0039] See also Figure 3 The intermediate frequency transceiver conversion switch is composed of two switches sw1 and sw2. In the transmitting mode, the switch sw1 is turned on, the switch sw2 is turned off, and the single-ended intermediate frequency signal input by the intermediate frequency port IF is sent to the intermediate frequency amplifier in the up-conversion link via the switch sw1. In the receiving mode, the switch sw2 is turned on, the switch sw1 is turned off, and the single-ended intermediate frequency signal output by the down-converter in the down-conversion link is output to the intermediate frequency port IF via the switch sw2. The intermediate frequency transceiver conversion switch can also be replaced by a single-pole double-throw switch.

[0040] See also Figure 4 The intermediate frequency amplifier is composed of a transformer Tr1 and an intermediate frequency variable gain amplifier IF VGA in cascade. The transformer Tr1 is used to realize the conversion from a single-ended intermediate frequency signal to a differential intermediate frequency signal, and the intermediate frequency variable gain amplifier IFVGA is used to amplify the differential intermediate frequency signal. The transformer Tr1 preferably adopts a low-coupling transformer to achieve good broadband matching. The gain of the intermediate frequency variable gain amplifier IF VGA is adjustable, which provides a certain dynamic range for the up-conversion link.

[0041] See also Figure 5 The hybrid coupler has two input terminals, two isolation terminals and four output terminals. The two input terminals receive the differential intermediate frequency signal output by the intermediate frequency amplifier. The two isolation terminals are connected to the resistor R ISO The two ends of the resistor R ISO Represents the load at the isolation end. The hybrid coupler converts two differential intermediate frequency signals (phase difference of 180 degrees) into four orthogonal intermediate frequency signals (phase difference of 90 degrees) and outputs them through four output terminals. The four output terminals are respectively connected to four DC blocking capacitors C1 to C4 to remove the DC component in the four orthogonal intermediate frequency signals. Preferably, the hybrid coupler adopts an on-chip transformer structure and only uses top metal and capacitors, which is conducive to reducing sensitivity to process, voltage and temperature changes.

[0042] See also Figure 5The orthogonal up-converter receives four orthogonal intermediate frequency signals from four DC blocking capacitors C1 to C4, and also receives four orthogonal local oscillator signals (with a phase difference of 90 degrees) from the local oscillator circuit. The orthogonal intermediate frequency signals and the orthogonal local oscillator signals are mixed in the orthogonal up-converter to output two differential RF signals. Because of the orthogonal characteristics, the differential RF signal output by the orthogonal up-converter is single-sideband and can effectively suppress the image signal. The two output ends of the orthogonal up-converter are connected to an RF balun transformer T1 (this is an optional device). The primary coil of the RF balun transformer T1 is connected in parallel with the capacitor array C arr , by adjusting the capacitor array C arr It can cover a wide frequency range. For example, the capacitor array C arr It is a programmable capacitor array. By adjusting the programmable capacitor array C arr To cover different frequency bands. The RF balun transformer T1 preferably adopts a low coupling transformer to achieve good broadband matching. The center tap of the primary coil of the RF balun transformer T1 is connected to the power supply voltage VDD.

[0043] See also Figure 6 The local oscillator circuit includes a transformer Tr2, a local oscillator input buffer (LO Input Buffer) B1, switches sw3 and sw4, a down-conversion link buffer B2, an orthogonal all-pass filter (QAF, quadrature all-pass filter), and an up-conversion link buffer B3 and B4.

[0044] In the transmitting mode, the working state of the local oscillator circuit is as follows. The single-ended local oscillator signal input by the local oscillator port LO is first converted into a differential local oscillator signal by transformer 2 Tr2, and the differential local oscillator signal is then amplified by the local oscillator input buffer B1 and sent to switch 3 sw3 and switch 4 sw4. Because the RF line is relatively long and the high-frequency signal is attenuated, the local oscillator input buffer B1 is inserted to compensate for the loss in amplitude and drive the next stage circuit. Switch 3 sw3 is turned on, switch 4 sw4 is turned off, and the differential local oscillator signal is transmitted to the orthogonal all-pass filter via switch 3 sw3. The function of the orthogonal all-pass filter is to generate an orthogonal signal. A broadband orthogonal signal can be generated by using only a single-stage orthogonal all-pass filter. The orthogonal all-pass filter converts two differential local oscillator signals (with a phase difference of 180 degrees) into four orthogonal local oscillator signals (with a phase difference of 90 degrees). Because it works in the millimeter wave frequency band, the inductor size is small and easy to design. The four orthogonal local oscillator signals generated by the orthogonal all-pass filter are amplified by the up-conversion link buffers B3 and B4 and then output to the orthogonal up-converter. In order to ensure that the orthogonal up-converter has sufficient conversion gain, a sufficiently large amplitude of the orthogonal local oscillator signal is required, so the up-conversion link buffers B3 and B4 are required to drive and amplify.

[0045] In the receiving mode, the working state of the local oscillator circuit is as follows. The single-ended local oscillator signal input by the local oscillator port LO is first converted into a differential local oscillator signal by transformer 2 Tr2, and the differential local oscillator signal is then amplified by the local oscillator input buffer B1 and sent to switch three sw3 and switch four sw4. Because the RF line is relatively long and the high-frequency signal is attenuated, the local oscillator input buffer B1 is inserted to compensate for the loss in amplitude and drive the next stage circuit. Switch four sw4 is turned on, switch three sw3 is turned off, and the two differential local oscillator signals are transmitted to the down-conversion link buffer B2 via switch four sw4. The down-conversion link buffer B2 amplifies the two differential local oscillator signals and outputs them to the down-converter. In order to ensure that the down-converter has sufficient conversion gain, a sufficiently large amplitude of the differential local oscillator signal is required, so the down-conversion link buffer B2 needs to drive and amplify.

[0046] Figure 6 In the local oscillator circuit shown, transformer 2 Tr2 is preferably a low-coupling transformer to achieve good broadband matching. Only one level of orthogonal all-pass filter is needed to convert the differential local oscillator signal into a broadband orthogonal local oscillator signal output, which has a small area, a large frequency range covered by the local oscillator signal, no power consumption, and low design complexity. An up-conversion link buffer is inserted after the orthogonal all-pass filter to achieve better signal quality, that is, to provide sufficient driving voltage to the orthogonal up-mixer.

[0047] See also Figure 7 The RF transceiver conversion switch is composed of two switches sw5 and sw6. In the transmitting mode, the switch 5 sw5 is turned on, the switch 6 sw6 is turned off, and the differential RF signal output by the orthogonal up-converter is transmitted to the RF balun transformer 2 T2 after passing through the switch 5 sw5. In the receiving mode, the switch 6 sw6 is turned on, the switch 5 sw5 is turned off, and the differential RF signal output by the RF balun transformer 2 T2 is sent to the down-converter via the switch 6 sw6.

[0048] See also Figure 7 , the RF balun transformer 2 T2 is used to realize the conversion between differential RF signals and single-ended RF signals. In the transmitting mode, the RF balun transformer 2 T2 converts the differential RF signal output by the RF transceiver conversion switch into a single-ended RF signal and sends it to the RF port RF output. In the receiving mode, the RF balun transformer 2 T2 converts the single-ended RF signal input by the RF port RF into a differential RF signal and sends it to the RF transceiver conversion switch. Preferably, the RF balun transformer 2 T2 adopts a low-coupling on-chip transformer, and the primary coil is connected in parallel with the capacitor C p1 , the secondary coil parallel capacitor C p2 Because the coupling coefficient is low, plus the two capacitors C in parallel p1 and C p2Two transmission poles are formed, and the RF balun transformer T2 achieves broadband matching. The center tap of the primary coil of the RF balun transformer T2 is grounded, which provides a fixed potential for the center tap, and the phase error and amplitude error of the differential signal are smaller.

[0049] See also Figure 8 The output end of the down converter is also connected to transformer 3 Tr3 (in Figure 2 The down converter is used to down-convert the differential RF signal output by the RF transceiver conversion switch into a differential intermediate frequency signal based on the differential local oscillator signal. Transformer 3 Tr3 is used to convert the differential intermediate frequency signal into a single-ended intermediate frequency signal, and then send it to the intermediate frequency transceiver conversion switch. Transformer 3 Tr3 preferably uses a low-coupling transformer to achieve good broadband matching.

[0050] Preferably, switch 1 sw1 and switch 2 sw2 in the intermediate frequency transceiver conversion switch, switch 3 sw3 and switch 4 sw4 in the local oscillator circuit, and switch 5 sw5 and switch 6 sw6 in the radio frequency transceiver conversion switch have the performance of low insertion loss and high isolation whether in the transmitting mode or in the receiving mode.

[0051] Preferably, the impedances of the intermediate frequency port IF, the radio frequency port RF and the local oscillator port LO are all matched to 50 ohms.

[0052] Compared with the prior art, the millimeter wave up and down conversion module proposed in this application has the following advantages.

[0053] First, only one-stage orthogonal all-pass filter is used to generate a broadband orthogonal local oscillator signal, which has a small area, a large frequency range covered by the orthogonal local oscillator signal (ie, it has broadband characteristics), no power consumption, and low design complexity.

[0054] Second, good image suppression and local oscillator leakage suppression can be achieved without the need for calibration circuits, greatly reducing the difficulty of circuit design. Image suppression is due to the orthogonal characteristics of the orthogonal up-converter. The differential RF signal output by the orthogonal up-converter is single-sideband, which can effectively suppress image signals. Local oscillator leakage suppression is due to the orthogonal up-converter using a total of four-channel orthogonal mixer structure with I differential and Q differential, and the down-converter using a two-channel differential structure. The differential structure can better suppress the leakage of the local oscillator signal.

[0055] Third, transformer 1 Tr1 and transformer 3 Tr3 near the intermediate frequency port IF, transformer 2 Tr2 near the local oscillator port LO, RF balun transformer 1 T1 and RF balun transformer 2 T2 near the radio frequency port RF are all low-coupling transformers, so a matching network based on low-coupling transformers is formed at the intermediate frequency port IF, the local oscillator port LO, and the radio frequency port RF, achieving broadband matching. Generally, a transformer with a coupling coefficient between 0.1 and 0.6 is called a low-coupling transformer.

[0056] Fourth, orthogonal up-converters and down-converters are based on active structures, and their gain is greater than that of traditional passive structures.

[0057] The above are only preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present application should all be included in the protection scope of the present application.

Claims

1. A millimeter wave up and down conversion module, characterized in that: It includes an intermediate frequency transceiver conversion switch and an RF transceiver conversion switch. There are two links between the two switches: an up-conversion link and a down-conversion link. The up-conversion link includes an intermediate frequency amplifier, a hybrid coupler, and an orthogonal up-converter in sequence. The down-conversion link includes a down-converter. The orthogonal up-converter and the down-converter are both active structures. There is also a local oscillator circuit that provides a local oscillator signal to the orthogonal up-converter and the down-converter. There is also a second RF balun transformer connected to the RF transceiver conversion switch. The hybrid coupler has two input terminals, two isolation terminals and four output terminals; the two input terminals receive the differential intermediate frequency signals output by the intermediate frequency amplifier; The two isolated terminals are connected to both ends of a resistor representing the load of the isolated terminals; The hybrid coupler converts two differential intermediate frequency signals into four orthogonal intermediate frequency signals and outputs them through four output terminals. The four output terminals are respectively connected to four DC blocking capacitors to remove DC components in the four orthogonal intermediate frequency signals. The millimeter wave up and down conversion module has two working modes: transmission mode and reception mode; In the transmission mode, the IF transceiver switch sends the IF signal input from the IF port to the up-conversion link; The intermediate frequency input signal is first converted from a single-ended intermediate frequency signal to a differential intermediate frequency signal and amplified by an intermediate frequency amplifier. The amplified differential intermediate frequency signal is then converted into an orthogonal intermediate frequency signal by a hybrid coupler and provided to an orthogonal up-converter. The local oscillator circuit converts the single-ended local oscillator signal inputted from the local oscillator port into an orthogonal local oscillator signal and provides it to the orthogonal up-converter; the orthogonal up-converter mixes the orthogonal intermediate frequency signal and the orthogonal local oscillator signal to obtain the radio frequency signal and then outputs it differentially; The RF transceiver conversion switch outputs the differential RF signal output by the orthogonal up-converter to the RF balun transformer 2; the RF balun transformer 2 converts the differential RF signal from the RF transceiver conversion switch into a single-ended RF signal and outputs it to the antenna at the RF port; In the receiving mode, the RF balun transformer 2 converts the single-ended RF signal received from the antenna at the RF port into a differential RF signal; the RF transceiver conversion switch sends the differential RF signal from the RF balun transformer 2 to the down-conversion link, specifically to the down-converter; the local oscillator circuit converts the single-ended local oscillator signal input at the local oscillator port into a differential local oscillator signal and provides it to the down-converter; the down-converter mixes the differential RF signal and the differential local oscillator signal to obtain a differential intermediate frequency signal, which is then converted into a single-ended intermediate frequency signal; The intermediate frequency transceiver conversion switch outputs the single-ended intermediate frequency signal output by the down converter at the intermediate frequency port.

2. The millimeter wave up-down conversion module according to claim 1 is characterized in that: The intermediate frequency transceiver conversion switch consists of switch one and switch two; in the transmitting mode, switch one is turned on and switch two is turned off, and the single-ended intermediate frequency signal input by the intermediate frequency port is sent to the intermediate frequency amplifier in the up-conversion link via switch one; in the receiving mode, switch two is turned on and switch one is turned off, and the single-ended intermediate frequency signal output by the down-converter in the down-conversion link is output to the intermediate frequency port via switch two.

3. The millimeter wave up-down conversion module according to claim 1 is characterized in that: The intermediate frequency amplifier is composed of a transformer 1 and an intermediate frequency variable gain amplifier in cascade; the transformer 1 is used to realize the conversion from a single-ended intermediate frequency signal to a differential intermediate frequency signal, and the intermediate frequency variable gain amplifier is used to amplify the differential intermediate frequency signal.

4. The millimeter wave up-down conversion module according to claim 1 is characterized in that: The orthogonal up-converter receives four orthogonal intermediate frequency signals and also receives four orthogonal local oscillator signals from the local oscillator circuit. The orthogonal intermediate frequency signals and the orthogonal local oscillator signals are mixed by the orthogonal up-converter to output two differential radio frequency signals.

5. The millimeter wave up-down conversion module according to claim 4 is characterized in that: The two output ends of the orthogonal up-converter are connected to a radio frequency balun transformer 1; the primary coil of the radio frequency balun transformer 1 is connected in parallel with a capacitor array, and the capacitor array is adjusted to cover different frequency bands.

6. The millimeter wave up-down conversion module according to claim 1 is characterized in that: The local oscillator circuit includes transformer 2, local oscillator input buffer, switch 3 and switch 4, down-conversion link buffer, orthogonal all-pass filter, and up-conversion link buffer; In the transmitting mode, the single-ended local oscillator signal inputted by the local oscillator port is first converted into a differential local oscillator signal by transformer 2, and the differential local oscillator signal is then amplified by the local oscillator input buffer and sent to switch 3 and switch 4; switch 3 is turned on, switch 4 is turned off, and the differential local oscillator signal is transmitted to the orthogonal all-pass filter via switch 3; the orthogonal all-pass filter converts the two-way differential local oscillator signal into four-way orthogonal local oscillator signal, which is amplified by the up-conversion link buffer and then outputted to the orthogonal up-converter; In the receiving mode, the single-ended local oscillator signal input to the local oscillator port is first converted into a differential local oscillator signal by transformer 2, and the differential local oscillator signal is then amplified by the local oscillator input buffer and sent to switch 3 and switch 4; switch 4 is turned on, switch 3 is turned off, and the differential local oscillator signal is transmitted to the down-conversion link buffer via switch 4; the down-conversion link buffer amplifies the two differential local oscillator signals and outputs them to the down-converter.

7. The millimeter wave up-down conversion module according to claim 1 is characterized in that: The RF transceiver conversion switch consists of switch five and switch six; in the transmitting mode, switch five is turned on and switch six is ​​turned off, and the differential RF signal output by the orthogonal up-converter is transmitted to the RF balun transformer two after passing through switch five; in the receiving mode, switch six is ​​turned on and switch five is turned off, and the differential RF signal output by the RF balun transformer two is sent to the down-converter via switch six.

8. The millimeter wave up-down conversion module according to claim 1 is characterized in that: The RF balun transformer 2 is used to realize the conversion between differential RF signals and single-ended RF signals; in the transmitting mode, the RF balun transformer 2 converts the differential RF signal output by the RF transceiver conversion switch into a single-ended RF signal and sends it to the RF port output; in the receiving mode, the RF balun transformer 2 converts the single-ended RF signal input by the RF port into a differential RF signal and sends it to the RF transceiver conversion switch.

9. The millimeter wave up-down conversion module according to claim 1, characterized in that: The output end of the down-converter is also connected to transformer three; the down-converter is used to down-convert the differential RF signal output by the RF transceiver conversion switch into a differential intermediate frequency signal based on the differential local oscillator signal; transformer three is used to convert the differential intermediate frequency signal into a single-ended intermediate frequency signal, and then send it to the intermediate frequency transceiver conversion switch.

10. The millimeter wave up-down conversion module according to claim 3, characterized in that: The transformer 1 is a low coupling transformer, which is used to achieve broadband matching.

11. The millimeter wave up-down conversion module according to claim 5, characterized in that: The RF balun transformer 1 is a low-coupling transformer used to achieve broadband matching.

12. The millimeter wave up-down conversion module according to claim 6, characterized in that: The second transformer is a low-coupling transformer, which is used to achieve broadband matching.

13. The millimeter wave up-down conversion module according to claim 8, characterized in that: The RF balun transformer 2 is a low-coupling transformer used to achieve broadband matching.

14. The millimeter wave up-down conversion module according to claim 9, characterized in that: The transformer three is a low coupling transformer, which is used to achieve broadband matching.

15. The millimeter wave up-down conversion module according to claim 2, characterized in that: The switch 1 and the switch 2 are switches with low insertion loss and high isolation.

16. The millimeter wave up-down conversion module according to claim 6, characterized in that: The switch three and switch four are switches with low insertion loss and high isolation.

17. The millimeter wave up-down conversion module according to claim 7, characterized in that: The switch five and the switch six are switches with low insertion loss and high isolation.

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