Hybrid antenna arrays with high angular resolution for 77 GHz automotive radars

Abstract

An antenna array system with high angular resolution is proposed to adapt the demands of both medium-range radar (MRR) and longrange radar (LRR) detections for 77 GHz automotive radars. Both the MRR and LRR modes are integrated into one substrate based on the optimized sparse array topology, which makes full use of the antenna aperture size to improve the angular resolution of the proposed system. Two-dimensional series-fed weighting arrays are designed via the Taylor synthesis method to effectively heighten the antenna gain and restrain the sidelobe level. After completing the fabrication, measurement results of the proposed antenna array are in good agreement with the simulation results. Moreover, the angular resolution is verified to be 0.5°by adopting the coherent signal space method (CSM) with stepped frequency transmitting waveform, which validates the effectiveness of the proposal.

Pitch and yaw angular speed measurement using Kalman data fusion

“…The measurement of angular speed is a topic because tachometers are required in a plethora of applications across many industries. Many methods and devices rely on counting pulses, which are associated with displacement by a fixed angle [10][11][12][13][14][15][16][17][18][19][20][21]. Most research has focused on the angular rotation speed.…”

Series-Fed Monopulse Microstrip Array Antenna With Stripline Quadrature Hybrid Comparator Network

“…In [19], six series-fed microstrip linear subarrays with tapered patch width distribution and a single-end connecting SIW parallel feed network were used to form shaped patterns in azimuth and elevation cut planes. In [20], a series of patches with tapered width and impedance transformers were utilized to form a planar microstrip array for automobile radar long range detection. An ideal first side lobe level (FSLL) of approximately -20 dB was achieved in its E and H planes.…”

“…This study further develops the planar series-fed array layout used in [20] to the Ka-band monopulse array antenna design. To suppress the FSLL in sum patterns, the Taylor synthesis method is used in the first quadrant planar array design, which is then mirror symmetrically arranged about xaxial and y-axial to obtain the four-quadrant front-end.…”

Ka-band microstrip array antenna with compact series-parallel hybrid strip-line feeding network

“…In addition, their low profile characteristics and light weight meet application requirements [5,6]. Motivated by these situations and the developing technology of printed circuit boards (PCBs), many types of substrate integrated waveguide (SIW) slot arrays [7,8] and series [9,10,11,12,13,14,15] or parallel [16,17,18,19,20,21] fed microstrip arrays are gradually replacing the traditional metallic waveguide or plate slot array antenna, as in [22,23]. Such PCB processing-based antennas have become the primary option in modern radar systems.…”

“…Such a structure may degrade the cross-polarization level, and the air gap used in [25] results in a thick antenna profile. References [13,24] employed a low-profile single-layer microstrip layout, but their edge feed method caused asymmetry of the antenna patterns to some extent. A dual-layer substrate and bottom-printed microstrip feeding were used in [26] to improve the asymmetry issue in [24], however, this structure had strong backward radiation.…”