阅读说明：本技术 一种正交变频接收机 (Orthogonal frequency conversion receiver ) 是由 陈鹏鹏 曹佳 陈鹏伟 彭尧 齐全文 于 2019-10-31 设计创作，主要内容包括：本发明公开一种正交变频接收机,应用于毫米波雷达收发系统,该正交变频接收机包括：一分四差分功率分配器及分别与该一分四差分功率分配器连接的四个接收通道,其中四个接收通道中的每个包括：低噪声放大器、正交混频器、正交信号发生器、驱动放大器、低通滤波器和可变增益放大器。本发明的正交变频接收机可配置低噪放,实现高输入P-1dB与低噪声系数,一分四差分功率分配器实现了无交叉高隔离度的本振信号分配,正交信号发生器实现了抗负载寄生的设计。另外,一分四功率分配器、正交信号发生器和低噪声发大器的综合设置保证了正交变频接收机的高线性与低噪声。(The invention discloses an orthogonal frequency conversion receiver, which is applied to a millimeter wave radar transceiving system and comprises: one-to-four differential power divider and four receiving channels respectively connected with the one-to-four differential power divider, wherein each of the four receiving channels comprises: low noise amplifier, quadrature mixer, quadrature signal generator, driver amplifier, low pass filter and variable gain amplifier. The orthogonal frequency conversion receiver can be configured with low noise amplification to realize high input P-1dB and low noise coefficient, the one-to-four differential power distributor realizes the local oscillator signal distribution without cross high isolation, and the orthogonal signal generator realizes the design of load spurious resistance. In addition, the comprehensive arrangement of the one-to-four power divider, the orthogonal signal generator and the low noise amplifier ensures high linearity and low noise of the orthogonal frequency conversion receiver.)

1. An orthogonal frequency conversion receiver applied to a millimeter wave radar transceiving system, the orthogonal frequency conversion receiver comprising:

the input end of the one-to-four differential power divider is used for inputting local oscillation signals; and

four receiving channels respectively connected to the one-to-four differential power divider, wherein each of the four receiving channels includes: a low noise amplifier, a quadrature mixer, a quadrature signal generator, a driver amplifier, a low pass filter, and a variable gain amplifier;

wherein for each receive channel: the input end of the driving amplifier is connected with the output end of the one-to-four power divider, the output end of the driving amplifier is connected to the first input end of the quadrature mixer through the quadrature signal generator, a radio frequency signal is sent to the second input end of the quadrature mixer through the low-noise amplifier, the output end of the quadrature mixer is connected to the input end of the variable gain amplifier through the low-pass filter, and the output end of the variable gain amplifier outputs an intermediate frequency output signal.

2. The quadrature receiver of claim 1 wherein the input and output signals of said one-to-four differential power divider are differential signals.

3. The quadrature receiver of claim 2, wherein said divide-by-four differential power divider comprises a first wilkinson power divider, a second wilkinson power divider, a first balun, a second balun, a third balun, and a fourth balun, wherein

The non-inverting input end of the differential signal input by the four-in-one differential power divider is connected to the input end of the first wilkinson power divider, the first output end of the first wilkinson power divider is connected to the input end of the first balun, and the second output end of the first wilkinson power divider is connected to the input end of the second balun;

an inverting input end of an input differential signal of the one-to-four differential power divider is connected to an input end of the second wilkinson power divider, a first output end of the second wilkinson power divider is connected to an input end of the third balun, and a second output end of the second wilkinson power divider is connected to an input end of the fourth balun;

and the output ends of the first balun, the second balun, the third balun and the fourth balun are used as the output ends of the four-in-one differential power divider for outputting differential signals.

4. The quadrature frequency conversion receiver of claim 1 wherein said quadrature signal generator is a wideband differential architecture.

5. The quadrature receiver of claim 4 wherein said quadrature signal generator comprises a first transmission line inductor, a second transmission line inductor, a first capacitor, a second capacitor, a first resistor and a second resistor, wherein

A first input terminal Vin + of the quadrature signal generator is connected to a first terminal of the first transmission line inductor and a first terminal of the first capacitor, a second terminal of the first capacitor is connected to a first terminal of the first resistor and a first output terminal Voi + of the quadrature signal generator, and a second terminal of the first transmission inductor is connected to a third output terminal Voq + of the quadrature signal generator;

a second input terminal Vin-of the quadrature signal generator is connected to a first terminal of the second transmission line inductor and a first terminal of the second capacitor, a second terminal of the second capacitor is connected to a first terminal of the second resistor and a second output terminal Voi-of the quadrature signal generator, a second terminal of the second resistor is connected to a third output terminal Voq + of the quadrature signal generator, and a second terminal of the second transmission inductor is connected to a second terminal of the first resistor and a fourth output terminal Voq-of the quadrature signal generator;

the first output terminal Voi + of the quadrature signal generator and the second output terminal Voi-of the quadrature signal generator are for providing an in-phase component, and the third output terminal Voq + of the quadrature signal generator and the fourth output terminal Voq-of the quadrature signal generator are for providing a quadrature component.

6. The quadrature frequency conversion receiver of claim 1, wherein said low noise amplifier is a segmented low noise amplifier.

7. The quadrature frequency conversion receiver of claim 6, wherein the low noise amplifier comprises a primary amplification stage, a post amplification stage, a first SPDT switch, a second SPDT switch, and a transmission line, wherein

The radio frequency signal is sent to the input end of the primary amplification stage, the output end of the primary amplification stage is connected with the input end of the first single-pole double-throw switch, the first output end of the first single-pole double-throw switch is connected to the input end of the rear amplification stage, the output end of the rear amplification stage is connected to the first input end of the second single-pole double-throw switch, the second output end of the first single-pole double-throw switch is connected to the second input end of the second single-pole double-throw switch through the transmission line, and the output end of the second single-pole double-throw switch is the output end of the low noise amplifier.

8. The quadrature frequency conversion receiver of claim 7, wherein said first single pole double throw switch and said second single pole double throw switch make a selection of a switching mode based on a magnitude of said radio frequency signal.

9. The quadrature frequency conversion receiver of claim 8,

when the radio frequency signal is less than a first threshold, the first single-pole double-throw switch selects the first output terminal, and the second single-pole double-throw switch selects the first input terminal;

when the radio frequency signal is greater than a second threshold, the first single pole double throw switch selects the second output terminal, and the second single pole double throw switch selects the second input terminal.

10. The orthogonal frequency conversion receiver of claim 9, wherein the first threshold is less than or equal to the second threshold.

Technical Field

The invention relates to the technical field of radio frequency receiving. And more particularly, to an orthogonal frequency conversion four-channel receiver applied to a millimeter wave radar transceiving system.

Background

With the high-speed development of wireless communication electronic technology, wireless communication puts higher and higher requirements on the integration level, flexibility, compatibility of communication systems, engineering applicability and the like of a receiver. The radio frequency receivers are of various types and different in specific implementation manners. The radio frequency receiver is a core structure in microwave radio frequency systems such as wireless communication, electronic warfare, radar systems and satellite loads, and is widely applied to various radar systems.

The radio frequency receiver is used for receiving, converting and amplifying radio frequency signals with low noise, amplifying intermediate frequency signals with unfixed level into fixed intermediate frequency level after automatic gain control, and is an important module influencing the performance of a radar system. Particularly, for a receiver operating in a millimeter wave band, a down-conversion process is mainly used, and then a demodulation process and the like are performed at a low frequency. The down-conversion receiver can be divided into single-phase down-conversion and quadrature down-conversion, wherein the single-phase down-conversion is suitable for frequency modulation continuous waves, the quadrature down-conversion is suitable for signals of any modulation mode, and the anti-interference performance is better than that of the single-phase down-conversion.

The main indexes of the radio frequency receiver are linearity and sensitivity. When the traditional radio frequency receiver is applied to a millimeter wave radar receiving and transmitting system, performance indexes such as linearity, sensitivity, noise coefficient and the like of the traditional radio frequency receiver cannot well meet requirements.

Therefore, it is desirable to provide a high-linearity low-noise orthogonal frequency conversion four-channel receiver applied to a millimeter wave radar transceiving system.

Disclosure of Invention

The invention aims to provide a high-linearity low-noise orthogonal frequency conversion four-channel receiver applied to a millimeter wave radar receiving and transmitting system, which is used for solving the problems of high noise and poor linearity of the existing millimeter wave receiver.

In order to achieve the purpose, the invention adopts the following technical scheme:

a quadrature frequency conversion receiver is applied to a millimeter wave radar transceiving system, and comprises:

the input end of the one-to-four differential power divider is used for inputting local oscillation signals; and

four receiving channels respectively connected to the one-to-four differential power divider, wherein each of the four receiving channels includes: a low noise amplifier, a quadrature mixer, a quadrature signal generator, a driver amplifier, a low pass filter, and a variable gain amplifier;

wherein for each receive channel: the input end of the driving amplifier is connected with the output end of the one-to-four power divider, the output end of the driving amplifier is connected to the first input end of the quadrature mixer through the quadrature signal generator, the radio-frequency signal is sent to the second input end of the quadrature mixer through the low-noise amplifier, the output end of the quadrature mixer is connected to the input end of the variable gain amplifier through the low-pass filter, and the output end of the variable gain amplifier outputs an intermediate-frequency output signal.

Preferably, the input and output signals of the one-to-four differential power divider are differential signals.

Further preferably, the one-to-four differential power divider comprises a first wilkinson power divider, a second wilkinson power divider, a first balun, a second balun, a third balun and a fourth balun, wherein

The non-inverting input end of an input differential signal of the one-four differential power divider is connected to the input end of the first Wilkinson power divider, the first output end of the first Wilkinson power divider is connected to the input end of the first balun, and the second output end of the first Wilkinson power divider is connected to the input end of the second balun;

the inverting input end of an input differential signal of the one-to-four differential power divider is connected to the input end of the second Wilkinson power divider, the first output end of the second Wilkinson power divider is connected to the input end of the third balun, and the second output end of the second Wilkinson power divider is connected to the input end of the fourth balun;

the output ends of the first balun, the second balun, the third balun and the fourth balun are used as the output ends of a four-in-one differential power divider for outputting differential signals.

In the invention, the input and output signals of the one-to-four differential power divider are differential signals, so that the layout without cross can be realized. The wiring of the passive element in the one-to-four differential power divider is not crossed, so that the two Wilkinson power dividers and the four baluns are designed by top-layer metal, and thus, the top-layer metal thickness of the chip is the minimum, and the signal attenuation is the weakest.

Preferably, the quadrature signal generator is a broadband differential architecture.

Further preferably, the quadrature signal generator comprises a first transmission line inductor, a second transmission line inductor, a first capacitor, a second capacitor, a first resistor and a second resistor, wherein

A first input end Vin + of the orthogonal signal generator is connected to a first end of the first transmission line inductor and a first end of the first capacitor, a second end of the first capacitor is connected to a first end of the first resistor and a first output end Voi + of the orthogonal signal generator, and a second end of the first transmission inductor is connected to a third output end Voq + of the orthogonal signal generator;

the second input terminal Vin-of the quadrature signal generator is connected to the first terminal of the second transmission line inductor and the first terminal of the second capacitor, the second terminal of the second capacitor is connected to the first terminal of the second resistor and the second output terminal Voi-of the quadrature signal generator, the second terminal of the second resistor is connected to the third output terminal Voq + of the quadrature signal generator, and the second terminal of the second transmission inductor is connected to the second terminal of the first resistor and the fourth output terminal Voq-of the quadrature signal generator;

the first output terminal Voi + of the quadrature signal generator and the second output terminal Voi-of the quadrature signal generator are for providing an in-phase component, and the third output terminal Voq + of the quadrature signal generator and the fourth output terminal Voq-of the quadrature signal generator are for providing a quadrature component.

Compared with a single-end orthogonal signal generator, the orthogonal signal generator has wider bandwidth and smaller load parasitic.

Preferably, the low noise amplifier is a segmented low noise amplifier.

Further preferably, the low noise amplifier includes a primary amplification stage, a post amplification stage, a first single-pole double-throw switch, a second single-pole double-throw switch, and a transmission line, wherein

The radio frequency signal is sent to the input end of the primary amplification stage, the output end of the primary amplification stage is connected with the input end of the first single-pole double-throw switch, the first output end of the first single-pole double-throw switch is connected to the input end of the rear amplification stage, the output end of the rear amplification stage is connected to the first input end of the second single-pole double-throw switch, the second output end of the first single-pole double-throw switch is connected to the second input end of the second single-pole double-throw switch through a transmission line, and the output end of the second single-pole double-throw switch is the output end of the low-noise amplifier.

Further preferably, the first single-pole double-throw switch and the second single-pole double-throw switch make selection of the switching mode based on the magnitude of the radio frequency signal.

It is further preferred that the first and second liquid crystal compositions,

when the radio-frequency signal is smaller than a first threshold value, the first single-pole double-throw switch selects the first output end, and the second single-pole double-throw switch selects the first input end;

when the radio frequency signal is larger than the second threshold value, the first single-pole double-throw switch selects the second output end, and the second single-pole double-throw switch selects the second input end.

Further preferably, the first threshold value is less than or equal to the second threshold value.

In the invention, two single-pole double-throw switches determine whether to adopt a rear amplification stage according to the magnitude of an input signal. When an input signal is small, the two single-pole double-throw switches are thrown at the position of the rear amplifier stage, so that the primary amplifier stage and the rear amplifier stage work simultaneously, and the maximum gain and the minimum noise coefficient are presented; when the input signal is large, the two single-pole double-throw switches are thrown at the position of the transmission line, so that the rear amplification stage does not work, the signal is amplified by the primary amplification stage and then transmitted to the output through the transmission line, and the maximum input P-1dB is presented.

The invention has the following beneficial effects:

the orthogonal frequency conversion receiver is applied to a millimeter wave radar receiving and transmitting system, can be configured with low noise amplification to realize high input P-1dB and low noise coefficient, can realize local oscillator signal distribution without cross high isolation by a one-to-four differential power distributor, and can realize the design of load parasitics resistance by an orthogonal signal generator. In addition, the comprehensive arrangement of the one-to-four power divider, the orthogonal signal generator and the low noise amplifier ensures high linearity and low noise of the orthogonal frequency conversion receiver.

Drawings

The following describes embodiments of the present invention in further detail with reference to the accompanying drawings.

Fig. 1 shows a block diagram of a quadrature frequency conversion receiving interface in the embodiment of the present invention.

Fig. 2 shows a block diagram of a one-to-four power divider according to an embodiment of the present invention.

Fig. 3 shows a block diagram of an orthogonal sign generator according to an embodiment of the present invention.

Fig. 4 shows a block diagram of a low noise amplifier according to an embodiment of the present invention.

Detailed Description

In order to more clearly illustrate the invention, the invention is further described below with reference to preferred embodiments and the accompanying drawings. Similar parts in the figures are denoted by the same reference numerals. It is to be understood by persons skilled in the art that the following detailed description is illustrative and not restrictive, and is not to be taken as limiting the scope of the invention.