On Self Driving Cars: An LED Time of Flight (ToF) based Detection and Ranging using various Unipolar Optical CDMA Codes

Suresh, Kasyap; Jeoti, Varun; Drieberg, Micheal; Iqbal, Amjid

doi:10.1109/icscc.2019.8843646

Cited by 6 publications

(3 citation statements)

References 6 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…35 In this scheme, strongly inspired by code division multiple access (CDMA) multiplexing technique from telecommunication theory, different pixels are modulated with different sequences, and the sequence family satisfies orthogonality conditions to avoid cross talk between pixels. From this point, research on this topic has focused on comparing and optimizing the modulation sequences, 36,37 proposing more complex sequence generation using wavelength division, 38 implementing hardware solutions to optimize the processing time, 39 or on considering this technique to ensure the robustness to interference from other lidars. 40 As for the experimental demonstration of this technique, implementations have only been made in kilohertz scanning devices, 41 hence using codes that were not compatible with fast scanning.…”

Section: Introductionmentioning

confidence: 99%

Overcoming the limitations of 3D sensors with wide field of view metasurface-enhanced scanning lidar

et al. 2023

View full text Add to dashboard Cite

Lidar, a technology at the heart of autonomous driving and robotic mobility, performs 3D imaging of a complex scene by measuring the time of flight of returning light pulses. Many technological challenges, including enhancement of the observation field of view (FoV), acceleration of the imaging frame rate, improvement of the ambiguity range, reduction of fabrication cost, and component size, must be simultaneously addressed so that lidar technology reaches the performance needed to strongly impact the global market. We propose an innovative solution to address the problem of wide FoV and extended unambiguous range using an acousto-optic modulator that rapidly scans a large-area metasurface deflector. We further exploit a multiplexing illumination technique traditionally deployed in the context of telecommunication theory to extend the ambiguity range and to drastically improve the signal-to-noise ratio of the measured signal. Compacting our metasurface-scanning lidar system to chip-scale dimension would open new and exciting perspectives, eventually relevant to the autonomous vehicles and robotic industries.

show abstract

Section: Introductionmentioning

confidence: 99%

Overcoming the limitations of 3D sensors with wide field of view metasurface-enhanced scanning lidar

et al. 2023

View full text Add to dashboard Cite

show abstract

“…In the United States, more than 5,000 pedestrians lost their lives due to road accidents and around 130,000 pedestrians needed medical treatments with non-fatal complications in 2015 [15]. Traffic death ratio can be minimized by using autonomous car techniques and devices [16], [17] which are capable of interacting with people [18].…”

Section: Introductionmentioning

confidence: 99%

Vision-Based Human Detection Techniques: A Descriptive Review

Sumit

Mirjalili

2021

IEEE Access

View full text Add to dashboard Cite

“…To alleviate the fundamental issues of pulsed-ToF measurements, including range ambiguity and frequent false detections, the applications of optical code-division multiple-access (OCDMA) modulation using 1-D unipolar time-spreading sequences, such as prime codes, modified prime codes, and optical orthogonal codes (OOCs) [8]- [12], were recently studied [13]- [15]. Each sensor was assigned a distinct time-spreading sequence.…”

Section: Introductionmentioning

confidence: 99%

2-D Optical-CDMA Modulation With Hard-Limiting for Automotive Time-of-Flight LiDAR

Yang

Lin

et al. 2021

IEEE Photonics J.

View full text Add to dashboard Cite

In this proof-of-principle paper, the application of 2-D optical code-division multiple-access (OCDMA) modulation to long-range automotive time-of-flight (ToF) light detection and ranging (LiDAR) is studied. The regulations and physical constraints that govern the design parameters are reviewed. Using 2-D carrier-hopping prime codes (CHPCs), the modulation model and a novel 2-D hard-limiting decoder are designed and validated with OptiSystem TM simulations. Based on the design parameters, the 2-D CHPCs have six times as many distinct sequences (for sensor identification) as 1-D code sequences. Analytical and simulation studies show that the proposed 2-D OCDMA modulation model can eliminate the near-far (power) problem and support more LiDAR sensors with distinctive ToF tags, greater interference robustness for more simultaneous ToF measurements, and better performance than the 1-D counterparts. The simulation results show that the 2-D model can support four times as many simultaneous emitting sensors without false detections as the 1-D model. In summary, the 2-D OCDMA modulation has more benefits and is more cost efficient overall, even though it is more complex.

show abstract

On Self Driving Cars: An LED Time of Flight (ToF) based Detection and Ranging using various Unipolar Optical CDMA Codes

Cited by 6 publications

References 6 publications

Overcoming the limitations of 3D sensors with wide field of view metasurface-enhanced scanning lidar

Overcoming the limitations of 3D sensors with wide field of view metasurface-enhanced scanning lidar

Vision-Based Human Detection Techniques: A Descriptive Review

2-D Optical-CDMA Modulation With Hard-Limiting for Automotive Time-of-Flight LiDAR

Contact Info

Product

Resources

About