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RF-to-DC characteristics of direct irradiated on-chip gallium arsenide Schottky diode and antenna for application in proximity communication system.

Mustafa F, Hashim AM - Sensors (Basel) (2014)

Bottom Line: It was found that the reduction of series resistance and parallel connection of diode and load tend to lead to the improvement of RF-to-DC conversion efficiency.Higher output voltage in volt range is expected to be achievable for the well-matching condition.The proposed on-chip AlGaAs/GaAs HEMT Schottky diode and antenna seems to be a promising candidate to be used for application in proximity communication system as a wireless low power source as well as a highly sensitive RF detector.

View Article: PubMed Central - PubMed

Affiliation: Faculty of Electrical Engineering, Universiti Teknologi Malaysia, Skudai, Johor 81310, Malaysia. farzies@gmail.com.

ABSTRACT
We report the RF-to-DC characteristics of the integrated AlGaAs/GaAs Schottky diode and antenna under the direct injection and irradiation condition. The conversion efficiency up to 80% under direct injection of 1 GHz signal to the diode was achieved. It was found that the reduction of series resistance and parallel connection of diode and load tend to lead to the improvement of RF-to-DC conversion efficiency. Under direct irradiation from antenna-to-antenna method, the output voltage of 35 mV was still obtainable for the distance of 8 cm between both antennas in spite of large mismatch in the resonant frequency between the diode and the connected antenna. Higher output voltage in volt range is expected to be achievable for the well-matching condition. The proposed on-chip AlGaAs/GaAs HEMT Schottky diode and antenna seems to be a promising candidate to be used for application in proximity communication system as a wireless low power source as well as a highly sensitive RF detector.

No MeSH data available.


Conversion efficiency as a function of input power at several frequencies.
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f7-sensors-14-03493: Conversion efficiency as a function of input power at several frequencies.

Mentions: Here, Pout is the DC power produced at the load resistance, RL and Pin is the injected power at the input side of diode. Figure 7 shows the measured conversion efficiency of the diode as a function of input power at different frequencies. Here, it can be seen that up to 80% conversion efficiency was obtained at frequency of 1 GHz which has been considered as the most optimum operating frequency of the fabricated diode. The rectification by direct injection should give the maximum conversion efficiency that is obtainable in the fabricated diode due to its minimal loss. From our previous study on individual diodes presented in [15], only 50% of the RF-DC conversion efficiency was obtained with a serial configuration of the diode and load. It is noted that the total resistance of the diode presented in [15] was 1.37 kΩ. Therefore, this seems to suggest that these two conditions: (1) reducing the total series resistance down to several Ω and (2) applying a parallel connection of diode and load may lead to improvement of the RF-to-DC conversion efficiency. As shown in Figure 2a, the diode is also modeled with a junction capacitance element, Cj. This capacitance determines the cut-off frequency of the diode as described in [31]. Therefore, both configurations of diode and load, i.e., series and parallel connection, should be able to generate RF-to-DC conversion characteristics within the range of the operating frequency of diode. As reported in [31], an additional external capacitor may be used to improve the stability of the DC output voltage. In this parallel connection, the built-in internal capacitor of the oscilloscope has been confirmed to be sufficient in producing stable DC output voltages. McSpadden et al. [29] also reported a high RF-to-DC conversion efficiency of 82% using a similar parallel connection of diode (5.8 GHz) and load (327 Ω).


RF-to-DC characteristics of direct irradiated on-chip gallium arsenide Schottky diode and antenna for application in proximity communication system.

Mustafa F, Hashim AM - Sensors (Basel) (2014)

Conversion efficiency as a function of input power at several frequencies.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3958227&req=5

f7-sensors-14-03493: Conversion efficiency as a function of input power at several frequencies.
Mentions: Here, Pout is the DC power produced at the load resistance, RL and Pin is the injected power at the input side of diode. Figure 7 shows the measured conversion efficiency of the diode as a function of input power at different frequencies. Here, it can be seen that up to 80% conversion efficiency was obtained at frequency of 1 GHz which has been considered as the most optimum operating frequency of the fabricated diode. The rectification by direct injection should give the maximum conversion efficiency that is obtainable in the fabricated diode due to its minimal loss. From our previous study on individual diodes presented in [15], only 50% of the RF-DC conversion efficiency was obtained with a serial configuration of the diode and load. It is noted that the total resistance of the diode presented in [15] was 1.37 kΩ. Therefore, this seems to suggest that these two conditions: (1) reducing the total series resistance down to several Ω and (2) applying a parallel connection of diode and load may lead to improvement of the RF-to-DC conversion efficiency. As shown in Figure 2a, the diode is also modeled with a junction capacitance element, Cj. This capacitance determines the cut-off frequency of the diode as described in [31]. Therefore, both configurations of diode and load, i.e., series and parallel connection, should be able to generate RF-to-DC conversion characteristics within the range of the operating frequency of diode. As reported in [31], an additional external capacitor may be used to improve the stability of the DC output voltage. In this parallel connection, the built-in internal capacitor of the oscilloscope has been confirmed to be sufficient in producing stable DC output voltages. McSpadden et al. [29] also reported a high RF-to-DC conversion efficiency of 82% using a similar parallel connection of diode (5.8 GHz) and load (327 Ω).

Bottom Line: It was found that the reduction of series resistance and parallel connection of diode and load tend to lead to the improvement of RF-to-DC conversion efficiency.Higher output voltage in volt range is expected to be achievable for the well-matching condition.The proposed on-chip AlGaAs/GaAs HEMT Schottky diode and antenna seems to be a promising candidate to be used for application in proximity communication system as a wireless low power source as well as a highly sensitive RF detector.

View Article: PubMed Central - PubMed

Affiliation: Faculty of Electrical Engineering, Universiti Teknologi Malaysia, Skudai, Johor 81310, Malaysia. farzies@gmail.com.

ABSTRACT
We report the RF-to-DC characteristics of the integrated AlGaAs/GaAs Schottky diode and antenna under the direct injection and irradiation condition. The conversion efficiency up to 80% under direct injection of 1 GHz signal to the diode was achieved. It was found that the reduction of series resistance and parallel connection of diode and load tend to lead to the improvement of RF-to-DC conversion efficiency. Under direct irradiation from antenna-to-antenna method, the output voltage of 35 mV was still obtainable for the distance of 8 cm between both antennas in spite of large mismatch in the resonant frequency between the diode and the connected antenna. Higher output voltage in volt range is expected to be achievable for the well-matching condition. The proposed on-chip AlGaAs/GaAs HEMT Schottky diode and antenna seems to be a promising candidate to be used for application in proximity communication system as a wireless low power source as well as a highly sensitive RF detector.

No MeSH data available.