Browsing by Author "Hung, Wei-Ping"

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A Variable Gain Envelope Modulator with Hybrid Topology for High Linearity/Efficiency Polar Transmitter Application
(2015)
Hung, Wei-Ping
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Chang, Chia-Hung
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傳播研究所
;
Institute of Communication Studies
An envelope modulator with hybrid topology for a high linearity and efficiency polar transmitter is described in this paper. The hybrid configuration exhibits a high speed and high efficiency combination by a linear amplifier and a switching amplifier, respectively, thereby improving the power added efficiency(PAE) of the polar transmitter. Moreover, to achieve wideband requirement, an operational trans-conductance amplifier with class AB output stage and variable gain function is designed in the linear amplifier. The switching amplifier adopts a buck converter design. The output dynamic range of envelope modulator shows a 5 dB variable gain with 1 dB resolution. The measured output voltage is from 0 similar to 3.5 V under the supply voltage of 3.5 V. The maximum driving power is 0.991 W for a 20 ohm loading.
Application of Smart Appliances to Wireless Area Network and Module Development
(2017-01-01)
Hung, Wei-Ping
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Lee, Tsern-Huei
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Chang, Chia-Hung
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電信工程研究所
;
Institute of Communications Engineering
In this paper, we implement the Wi-Fi hardware architecture. The core chip designed by the MediaTek Corporation is used to develop its peripheral circuits. The chip supports USB Type and can control the lighting circuit through the APP on the mobile phone, so as to simulate the switch of household electrical appliances. In the future, consumers can purchase home appliances with built-in communication modules and integrate them with the Home Energy Management System (HEMS), which can be used to control wireless energy-saving.
Automobile Anti-Collision Warning Radar Antennas with Tapered Excitations at Millimeter Wave Frequencies and their Design Consideration
(2019-01-01)
Ho, Shih-Kai
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Chou, Hsi-Tseng
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Hung, Wei-Ping
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電信工程研究所
;
Institute of Communications Engineering
In this paper, a set of phased arrays of antennas are developed for automobile anti-collision warning applications at 76GHz of millimeter wave (mmW) frequencies. This antenna set consists of two 16X8 and one 16x1 series-fed tapered antenna arrays for both long- and short-distance target detections. This antenna set has a radiation gain up to 24dBi and relative sidelobe level of smaller than-20dB in both E- and H planes by implementing a Dolph-Chebyshev distribution of excitation weightings. The return loss of power divider is lower than 25dB. The design consideration incorporating the PCB board effects is also studied to examine the radiation distortion in practical applications. Numerical simulation results are shown to validate the radiation phenomenon while measured data will be shown in the conference presentation.
Non-invasive Detection of Object by UWB Radar
(2017-01-01)
Hung, Wei-Ping
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Lee, Tsern-Huei
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Chang, Chia-Hung
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電信工程研究所
;
Institute of Communications Engineering
The use of UWB system front-end matching with the antenna from the VCO side adjustment, the key in the vicinity of the VCO circuit matching adjustment; because eight antennas, each antenna will have some slight differences in matching, resulting in the received DC value is not Will be in the same level, and the switch circuit in the switch antenna, it will allow a peak level (about 100ms), and switch the antenna when switching about 420ms similar to 480ms or so. In order to improve the above problem, when switching to the antenna, a variable of the calculation time is used as the current switching antenna, and the time of the switching of the antenna is changed, The time at the time of the operation is changed by 60 ms due to the switching time. As mentioned above, the calculated time will not be a constant value. Therefore, the remainder is divided by a constant, since the value of the first 100 ms can not be used, So to take the signal between 200ms similar to 400ms in order to correctly reflect the antenna front of the object of the reflected signal; After modifying the above problem, the software interface can detect whether there are metal objects in front of the antenna, and L-shaped steel plate to do experiments, The results show that the L pattern can be displayed on the screen; follow-up planning of a variety of different materials of the metal material corresponding to the DC level, and the use of statistical methods can be further accurate analysis of different metal types, the future can be extended application of Homeland Security Survey, Metal material detection and other areas
On Investigation of Near-field Antenna for Pulse based Vital-sign Monitoring Application
(2018-01-01)
Chang, Chia-Hung
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Hung, Wei-Ping
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電信工程研究所
;
Institute of Communications Engineering
This paper presents a pulsed-based vital-sign monitoring system using a comb-shaped antenna for wearable application. Two prototypes of near-field antenna are designed to investigate the performance of the received physiological signal on the wrist artery of a subject. The real-time, non-contact, and compact sensing module is analyzed, designed, and implemented.
Real-Time and Noncontact Impulse Radio Radar System for mu m Movement Accuracy and Vital-Sign Monitoring Applications
(2017-04-15)
Hung, Wei-Ping
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Chang, Chia-Hung
;
Lee, Tsern-Huei
;
電信工程研究所
;
Institute of Communications Engineering
In this paper, a real-time, contactless pulse-based ultra-wideband (UWB) radar sensor was used to precisely detect the movement of the robotic arm, heartbeats, and respiration activities. To increase the object tracking resolution, an algorithm using adaptive and digitalized post-calibration techniques were proposed and tested. Both the radiated and reflected analog pulses were converted to digital signals by a low-noise comparator and its buffer for the time interval and distance detection. Moreover, the dynamic and calibrated tracking mechanism was incorporated into the algorithm for improving tracking accuracy and to continuously localize an object's vibration. The measured performance revealed that the proposed method successfully achieved mu m movement precision, thus providing its excellent tracking ability. We performed three different experimental tests to demonstrate the UWB radar's viability. First, the radar was employed to detect the undesired structural vibration of a delta robotic arm, which was subjected to high acceleration and structural flexibility. The measured results indicated that the accuracy of 100 mu m can be achieved at a 10 Hz vibration frequency. Next, the apnea alarm was tested, which included an embedded sensitive sensor in the smart mattress in order to execute long-term physiological monitoring. The apnea was mitigated by auto-adjusting the patient's sleeping posture on the mattress when the UWB sensor detected the apnea condition. The final experiment using the radar sensor was to monitor human vital signs, such as heart and breathing rates, simultaneously. In comparison with a commercial electrocardiography instrument, this radar sensor measured 73.2 bpm with only 1.2% deviation. Our results shown that the contactless UWB sensor performs superbly and is well-suited for monitoring physiological parameters.