Ultra-wideband radar pulse generator realizing wide tuning range

Abstract

The present invention relates to an ultra-wideband radar pulse generator realizing a wide tuning range. The ultra-wideband radar pulse generator comprises a tunable-pulse-width rectangular pulse generator module and a high-frequency LC oscillator circuit module, which are connected to each other, wherein the tunable-pulse-width rectangular pulse generator module comprises a logic XOR gate and a controllable delay unit, and the logic XOR gate is used for generating a rectangular pulse signal; the high-frequency LC oscillator circuit comprises transistors Mp1, Mp2, inductors L1, L2, voltage-controlled variable capacitors Vc1, Vc2, and a current source It; L1 and Vc1 together with L2 and Vc2 form a pair of differential LC oscillating circuits; and a drain electrode of Mp1 is connected to a gate electrode of Mp2, and a drain electrode of Mp2 is connected to a gate electrode of Mp1. In the present invention, a relatively wide pulse width tuning range is achieved on the basis of a Gaussian-envelope UWB pulse generator architecture, and the detection precision of a radar sensor can be effectively improved, while it is ensured that the shape of an output pulse meets FCC spectral density requirements, and thus the application range of the radar sensor is widened.

Description

An ultra-wideband radar pulse generator with a wide tuning range Technical Field

[0001] The present invention relates to the field of integrated circuits, and in particular to an ultra-wideband radar pulse generator architecture with a wide tuning range. Background Art

[0002] The US Federal Communications Commission (FCC) has allocated the 3.1 GHz to 10.6 GHz frequency band for ultra-wideband (UWB) applications, but it also limits the power spectral density (PSD) of UWB output signals to no higher than -41.3 dBm / MHz. Frequency bands below 3 GHz are more crowded and have higher PSD limits for interfering signals (for example, in the GPS band, the PSD must be below -75.3 dBm / MHz). The 5 GHz to 6 GHz band also presents interference issues for WLAN narrowband communication systems. Due to the high level of interference and regulatory spectral density restrictions in the UWB band, pulse generators must exhibit fast response speeds and high-quality pulse morphology. Therefore, designing a UWB pulse generator with fast response speeds and excellent pulse morphology is a pressing issue.

[0003] Summary of the Invention

[0004] The present invention aims to provide an ultra-wideband radar pulse generator with a wide tuning range. Based on a Gaussian envelope UWB pulse generator architecture, the generator achieves a wide pulse width tuning range. This ensures that the output pulse morphology meets FCC spectral density requirements, effectively improving the detection accuracy of radar sensors and broadening their application range.

[0005] The present invention is implemented through the following technical solution: an ultra-wideband radar pulse generator with a wide tuning range, characterized in that:

[0006] It includes an adjustable pulse width rectangular pulse generator module and a high-frequency LC oscillator circuit module that are connected to each other;

[0007] The adjustable pulse width rectangular pulse generator module includes

[0008] a logic XOR gate for receiving an external clock signal; and

[0009] A controllable delay unit is connected to the logic XOR gate, receives an external clock signal and adjusts the delay time amount to send to the logic XOR gate;

[0010] Among them, the logic XOR gate generates a rectangular pulse signal by performing XOR operation on two clock signals;

[0011] The high frequency LC oscillator circuit includes a transistor M p1 , transistor Mp2 , inductor L1, inductor L2, voltage-controlled variable capacitor V c1 , voltage-controlled variable capacitor V c2 and the current source I t ;

[0012] The inductor L1 and the voltage-controlled variable capacitor V c1 , inductor L2 and voltage-controlled variable capacitor V c2 A pair of differential LC oscillation circuits are formed;

[0013] Transistor M p1 The drain of transistor M p2 The gate of transistor M is connected to p2 The drain of transistor M p1 The gate of the current source I t Connect transistor M p1 and transistor M p2 The source of

[0014] Transistor M p1 The drain, inductor L1 and voltage-controlled variable capacitor V c1 Connection, transistor M p2 The drain, inductor L2 and voltage-controlled variable capacitor V c2 connect;

[0015] Differential output vop connected to transistor M p1 The drain of the differential output von is connected to the transistor M p2 The drain;

[0016] The logic XOR gate and the current source I t connect.

[0017] Compared with the prior art, the present invention has the following beneficial effects:

[0018] 1. Within the specified signal spectrum power limit, a wide pulse width tuning range can be achieved. The controllable delay unit has a fast response speed and adjustable pulse width, which can improve the distance resolution and detection accuracy of the radar system. At the same time, the output of the adjustable pulse width rectangular pulse generator circuit module serves as the control signal of the high-frequency LC oscillator circuit module, which can effectively reduce the static power consumption of the circuit. The passive devices designed based on the back metal layer provided by the CMOS process can effectively improve the noise resistance performance of the overall circuit. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] FIG1 is a diagram showing the overall structure of the present invention. DETAILED DESCRIPTION

[0020] The present invention is described in detail below with reference to the accompanying drawings:

[0021] As shown in Figure 1: An ultra-wideband radar pulse generator with a wide tuning range includes an adjustable pulse width rectangular pulse generator module and a high-frequency LC oscillator circuit module connected to each other;

[0022] The adjustable pulse width rectangular pulse generator module includes

[0023] a logic XOR gate for receiving an external clock signal; and

[0024] A controllable delay unit is connected to the logic XOR gate, receives an external clock signal and adjusts the delay time amount to send to the logic XOR gate;

[0025] Among them, the logic XOR gate generates a rectangular pulse signal by performing XOR operation on two clock signals;

[0026] The high frequency LC oscillator circuit includes a transistor M p1 , transistor M p2 , inductor L1, inductor L2, voltage-controlled variable capacitor V c1 , voltage-controlled variable capacitor V c2 and the current source I t ;

[0027] The inductor L1 and the voltage-controlled variable capacitor V c1 , inductor L2 and voltage-controlled variable capacitor V c2 A pair of differential LC oscillation circuits are formed;

[0028] Transistor M p1 The drain of transistor M p2 The gate of transistor M is connected to p2 The drain of transistor M p1 The gate of the current source I t Connect transistor M p1 and transistor M p2 The source of

[0029] Transistor M p1 The drain, inductor L1 and voltage-controlled variable capacitor V c1 Connection, transistor M p2 The drain, inductor L2 and voltage-controlled variable capacitor V c2 connect;

[0030] Differential output vop connected to transistor M p1 The drain of the differential output von is connected to the transistor M p2 The drain;

[0031] The logic XOR gate and the current source I t connect.

[0032] Furthermore, the specific connection method of the differential LC oscillation circuit is:

[0033] One end of the inductor L1 and one end of the inductor L2 are connected to each other and grounded; the other end of the inductor L1 is connected to the voltage-controlled variable capacitor V c1 One end and the other end of the inductor L2 are connected to the voltage-controlled variable capacitor V c2 ; Voltage controlled variable capacitor V c1 and voltage-controlled variable capacitor V c2 The other end and the voltage-controlled variable capacitor V c2 The other ends are connected to each other and to the connection terminals.

[0034] In the present invention, an external clock signal is divided into two paths. One clock signal is fed into a logic XOR gate via a controllable delay unit, while the other signal is fed directly into the logic XOR gate without passing through the controllable delay unit. Based on the logical relationship characteristics of the logic XOR gate, the two clock signals are subjected to an XOR operation to generate a rectangular pulse. The controllable delay unit is composed of a group of delay cells with definable delay times. Therefore, the phase difference between the two input signals can be varied by adjusting the delay time of the delay circuit. Ultimately, the XOR operation through the logic XOR gate changes the pulse width of the output rectangular pulse signal.

[0035] It should be noted that the present invention is based on the characteristics of high-order CMOS semiconductor technology that is easy to integrate digital circuits and high-frequency LC oscillators. Through deep submicron CMOS technology, the minimum delay time of the controllable delay unit can reach femtoseconds, and the working range can meet the rectangular pulse signal with a wide pulse width tuning range.

[0036] The proposed high frequency LC oscillator circuit module includes a transistor M p1 , transistor M p2 ; Inductor L1, inductor L2; voltage-controlled variable capacitor V c1 , voltage-controlled variable capacitor V c2 The high-frequency LC oscillator has an adjustable resonant frequency and can generate a sine wave signal up to 10GHz. The inductor L1 and the voltage-controlled variable capacitor V c1 , inductor L2 and voltage-controlled variable capacitor V c2 A pair of differential LC oscillation circuits are formed, and the resonant frequency is Among them L tot =L1||L2,C tot =V c1 ||V c2 ; Therefore, by changing the voltage-controlled variable capacitor V c1 / V c2 The capacitance value can change the LC oscillation frequency;

[0037] Transistor M p1 The drain of transistor M p2 The gate is connected to the transistor Mp2 The drain of transistor M p1 The gates are connected to form a MOS switch; negative impedance is generated through cross coupling, and its main function is to provide oscillation energy for the LC oscillator to maintain the normal operation of the entire voltage-controlled oscillator. p1 With transistor M p2 Specifically, a differential PMOS transistor.

[0038] Current source I t M p1 and M p2 Provides DC bias current.

[0039] In the present invention, both the inductor L1 and the inductor L2 are high-Q on-chip spiral inductors processed based on CMOS technology. In addition, the logic XOR gate is connected to the current source It via a switch with an external power supply.

[0040] The output pulse signal from the adjustable-width rectangular pulse generator works in conjunction with the MOS switch to control the bias current of the LC oscillator. Therefore, the high-frequency LC oscillator circuit module operates normally and outputs a differential oscillating sinusoidal signal only when the output signal from the adjustable-width rectangular pulse generator module is high. When the output signal from the adjustable-width rectangular pulse generator module is low, the high-frequency LC oscillator circuit module is in standby mode.

[0041] Based on the back metal layer provided by the CMOS process, the inductors L1 and L2 of the high-frequency LC oscillator circuit module can be designed as high-Q on-chip spiral inductors, further improving the amplitude of the high-frequency LC oscillator circuit module and reducing phase noise.

[0042] Finally, it should be noted that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or make equivalent replacements for some of the technical features therein. 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. An ultra-wideband radar pulse generator with a wide tuning range, characterized in that: It includes an interconnected adjustable pulse-width rectangular pulse generator module and a high-frequency LC oscillator circuit module; The adjustable pulse-width rectangular pulse generator module includes a logical exclusive-OR gate for receiving an external clock signal; and a controllable delay unit connected to the logical exclusive-OR gate, receiving the external clock signal and adjusting the delay time amount to send to the logical exclusive-OR gate; wherein, the logical exclusive-OR gate generates a rectangular pulse signal by performing an exclusive-OR operation on two paths of clock signals; The high-frequency LC oscillator circuit includes transistor M p1 , transistor M p2 , inductor L1, inductor L2, voltage-controlled variable capacitor V c1 , voltage-controlled variable capacitor V c2 and current source I t ; The inductor L1 and the voltage-controlled variable capacitor V c1 , the inductor L2 and the voltage-controlled variable capacitor V c2 constitute a pair of differential LC oscillator circuits; Transistor M p1 The drain of which is connected to the gate of transistor M p2 The drain of transistor M p2 is connected to the gate of transistor M p1 ; The current source I t is connected to the sources of transistor M p1 and transistor M p2 . Transistor M p1 has its drain connected to inductor L1 and voltage-controlled variable capacitor V c1 ; transistor M p2 has its drain connected to inductor L2 and voltage-controlled variable capacitor V c2 ; The differential output vop is connected to the drain of transistor M p1 and the differential output von is connected to the drain of transistor M p2 ; Among them, the exclusive OR gate is connected to the current source I t Connected 2. The ultra-wideband radar pulse generator with a wide tuning range according to claim 1, characterized in that: The specific connection mode of the differential LC oscillation circuit is One end of inductor L1 and one end of inductor L2 are connected to each other and grounded; the other end of inductor L1 is connected to varactor V c1 One end and the other end of inductor L2 are connected to varactor V c2 ; Varactor V c1 And varactor V c2 The other end and the other end of varactor V c2 Are connected to each other and connected to the terminal.

3. The ultra-wideband radar pulse generator with a wide tuning range according to claim 1 or 2, characterized in that: Both the inductor L1 and the inductor L2 are high-Q on-chip spiral inductors processed based on the CMOS process.

4. The ultra-wideband radar pulse generator with a wide tuning range according to claim 1, characterized in that: wherein the exclusive OR gate is connected to the current source I through a switch with an external power supply t connected

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