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For the Internet of Things (IoT) beacon wireless communication scenario of Bluetooth Low Energy (BLE), this paper proposes a low-cost, long-range and low-power customized BLE simplified MAC protocol. According to the application scenarios of the protocol, the functional modules required by the protocol are analyzed and designed. RTL-level coding and simulation by the VCS, FPGA testing and verification of the protocol with Vivado development tools. The legacy broadcast function of BLE5.0 standard protocol and the 4 times communication range function of legacy broadcast are realized. In terms of FPGA resource usage, the protocol saves 67.2% LUT, 55.9% FF and a DSP (for frequency hopping algorithms2) compared with the full-featured BLE5.0 standard protocol.

For the application scenario of short-range, high speed wireless communication between consumer AR glasses terminal and smart phones, a customized wireless MAC protocol with ultra-high speed, low power, low latency characteristics is presented. First, based on the requirements of the application scenario, quantitative analysis of specifications such as effective throughput and latency are presented, then the detailed protocol is designed through the specifications above. Compared to the existing ECMA-398 protocol, the effective throughput standard S increased from 71% to 86%. By introducing priority mechanism for various type of data transmission, the maximum transmission latency is reduced by one order of magnitude, which is less than 1mS. This paper completed the construction and simulation of system-level models, RTL-level coding and verification according to the analysis above. Finally, the protocol was tested and verified through the FPGA platform. Simulation and test results show that the customized MAC protocol designed in this paper can fulfill the requirement of the scenario much better.

Dual-band and wide-band lenses covering both the MWIR and LWIR spectral bands are increasingly needed as dualband MWIR/LWIR detectors have become prevalent and broadband applications have expanded. Currently in dual-band /wide-band applications, the use of more than three elements per lens group and the use of chalcogenide glass is common. This results in expensive systems. Also, many chalcogenides are available only in small diameters, which is a problem for large aperture broadband lenses. In this paper an investigation of cost-effective designs for dual-band MWIR/LWIR lens using only widely available IR materials, specifically Ge, ZnSe and ZnS were performed. An athermalized dual-band MWIR/LWIR using these three materials is presented. The performance analysis of this lens shows that this design form with these three common IR materials works well in certain applications. The required large size blanks of these materials can be easily obtained. Traditional chromatic aberration correction without diffraction for either wide-band or dual-band application was employed. In addition, the methods of harmonic diffraction for dual-band applications, especially with one narrow band, were used for two different presented designs.

Previously, we showed that two- and three-band color-mixing techniques could be used to achieve results optically equivalent to two- and three-band ratios that are normally implemented using multispectral imaging systems, for enhancing identification of single target types against a background and for separation of multiple targets by color or contrast. In this paper, a prototype of a wavelength-changeable two- and three-band color-mixing device is presented and its application is demonstrated. The wavelength-changeable device uses changeable central wavelength bandpass filters and various filter arrangements. The experiments showed that a color-mixing technique implemented in a pair of binoculars coupled with an imager could greatly enhance target identification of color-blindness test cards with hidden numbers and figures as the targets. Target identification of color blindness cards was greatly improved by using twoband color-mixing with filters at 620 nm and 650 nm, which were selected based on the criterion of uniform background. Target identification of a different set of color blindness test cards was also improved using three-band color-mixing with filters at 450 nm, 520 nm, and 632 nm, which were selected based on the criterion of maximum chromaticness difference. These experiments show that color-mixing techniques can significantly enhance electronic imaging and visual inspection.

A three-color mixing application for food safety inspection is presented. It is shown that the chromaticness of the visual signal resulting from the three-color mixing achieved through our device is directly related to the three-band ratio of light intensity at three selected wavebands. An optical visual device using three-color mixing to implement the three-band ratio criterion is presented. Inspection through human vision assisted by an optical device that implements the three-band ratio criterion would offer flexibility and significant cost savings as compared to inspection with a multispectral machine vision system that implements the same criterion. Example applications of this optical three-color mixing technique are given for the inspection of chicken carcasses with various diseases and for apples with fecal contamination. With proper selection of the three narrow wavebands, discrimination by chromaticness that has a direct relation with the three-band ratio can work very well. In particular, compared with the previously presented two-color mixing application, the conditions of chicken carcasses were more easily identified using the three-color mixing application. The novel three-color mixing technique for visual inspection can be implemented on visual devices for a variety of applications, ranging from target detection to food safety inspection.

We show that the chromaticness of the visual signal that results from the two-color mixing achieved through an optically enhanced binocular device is directly related to the band ratio of light intensity at the two selected wavebands. A technique that implements the band-ratio criterion in a visual device by using two-color mixing is presented here. The device will allow inspectors to identify targets visually in accordance with a two-wavelength band ratio. It is a method of inspection by human vision assisted by an optical device, which offers greater flexibility and better cost savings than a multispectral machine vision system that implements the band-ratio criterion. With proper selection of the two narrow wavebands, discrimination by chromaticness that is directly related to the band ratio can work well. An example application of this technique for the inspection of carcasses chickens of afficted with various diseases is given. An optimal pair of wavelengths of 454 and 578 nm was selected to optimize differences in saturation and hue in CIE LUV color space among different types of target. Another example application, for the detection of chilling injury in cucumbers, is given, here the selected wavelength pair was 504 and 652 nm. The novel two-color mixing technique for visual inspection can be included in visual devices for various applications, ranging from target detection to food safety inspection.

In this paper, color-mixing applications for food safety and quality was studied, including two-color mixing and three-color mixing. It was shown that the chromaticness of the visual signal resulting from two- or three-color mixing is directly related to the band ratio of light intensity at the two or three selected wavebands. An optical visual device using color mixing to implement the band ratio criterion was presented. Inspection through human vision assisted by an optical device that implements the band ratio criterion would offer flexibility and significant cost savings as compared to inspection with a multispectral machine vision system that implements the same criterion. Example applications of this optical color mixing technique were given for the inspection of chicken carcasses with various diseases and for the detection of chilling injury in cucumbers. Simulation results showed that discrimination by chromaticness that has a direct relation with band ratio can work very well with proper selection of the two or three narrow wavebands. This novel color mixing technique for visual inspection can be implemented on visual devices for a variety of applications, ranging from target detection to food safety inspection.

Visual inspection of wholesome and unwholesome chicken carcasses with a novel two-narrowband color-mixing technique for optically enhanced binoculars is simulated. From mean spectra of wholesome, airsacculitis (air-sac), cadaver, inflammatory process (IP), septicemia–toxemia (septox), and tumor chicken samples, 10 nm wave-band pairs are selected using color difference and chromaticness difference indices for simulation of multitarget and single-target detection. The color appearance simulation uses the CIECAM97s color appearance model. Results show that for multitarget detection, the wave-band pair of (454 nm, 578 nm) is able to differentiate all six chicken conditions. For single-target detection of wholesome, air-sac, cadaver, and tumor, the wave-band pairs of (449 nm, 571 nm), (441 nm, 576 nm), (458 nm, 576 nm), and (431 nm, 501 nm), respectively, easily distinguish the target condition from the other five conditions. For single-target detection of IP and septox, the wave-band pairs of (454 nm, 591 nm) and (454 nm, 590 nm), respectively, are able to differentiate the target conditions from wholesome and tumor conditions but have difficulty with the other chicken conditions. The two-color-mixing technique shows promise for use in small-scale processing plant environments to improve the visual inspection process.

Development of an automated inspection system will help the poultry processing industry to provide better chicken products for the consumer while minimizing potential economic losses. The objective of this research was to investigate the potential of a color-based sensing technique suitable for rapid automated inspection for wholesomeness of chickens in the visible region between 400 nm and 700 nm. Spectra of veterinarian-selected carcasses, 400 wholesome and 332 unwholesome were collected from a high-speed processing plant kill line using a visible/near-infrared spectrophotometer system. CIELUV color differences characterizing wholesome and unwholesome chicken samples were calculated as a simple distance formula and used to classify individual samples. Results showed that the greatest color differences occurred for waveband combinations at (508 nm, 426 nm), (560 nm, 426 nm), and (640 nm, 420 nm). Full-spectrum classification achieved accuracies of 85%, 86%, 84%, and 82% for wholesome validation samples, wholesome testing samples, unwholesome validation samples, and unwholesome testing samples, respectively. Using the (560 nm, 426 nm) waveband combination, classification accuracies of 91%, 92%, 90%, and 90% were achieved for wholesome validation samples, wholesome testing samples, unwholesome validation samples, and unwholesome testing samples, respectively. The potential of using CIELUV color differences to differentiate between wholesome and unwholesome chickens was demonstrated, and the straightforward calculation involved suggest that the method is suitable for rapid automated online sorting of chicken carcasses.

Previous studies showed that two- and three-waveband color-mixing methods perform the optical equivalent of two- and three-wavelength band ratio calculations that are typically implemented using multispectral imaging to enhance target classification and detection. This paper presents a prototype two-waveband color-mixing binocular device for enhancing visual target detection and classification, as tested using Ishihara test cards. Target identification for the test cards in this study was improved by using two-waveband color-mixing binoculars fitted with filters centered at wavelength pairs selected according to the criterion of uniform background. The test-card imaging results demonstrate that color-mixing binoculars can be used to greatly enhance target identification and detection.