Large Dynamic Range and High Sensitivity Receiver in TCAS and Mode S Based on Digital Automatic Gain Control

The bandwidth and the dynamic range is the critical performance parameter of IF AGC (Intermediate Frequency Automatic Gain Control) in wireless receiver. In order to design broadband and large dynamic range IF AGC circuit, the main functions and performance of the VGA (Variable Gain Amplifier) AD8367 and the logarithmic amplifier AD8318 are analyzed. A kind of a broadband large dynamic range IF AGC module is designed by using these two chips. Detail circuit is provided; key technology of AGC module is analyzed and the actual testing results are offered. Compared to the traditional AGC circuit, the module is simple; it has small size and obvious advantages in broadband and large dynamic range.

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2.5 Gbit/s Optical Receiver Front-End Circuit with High Sensitivity and Wide Dynamic Range

Journal of Optical Communications ◽

10.1515/joc-2016-0030 ◽

2017 ◽

Vol 38 (4) ◽

Author(s):

Tiezhu Zhu ◽

Taishan Mo ◽

Tianchun Ye

Keyword(s):

Dynamic Range ◽

Automatic Gain Control ◽

Optical Network ◽

Gain Control ◽

High Sensitivity ◽

Cmos Technology ◽

Optical Receiver ◽

Passive Optical Network ◽

Wide Dynamic Range ◽

Front End

AbstractAn optical receiver front-end circuit is designed for passive optical network and fabricated in a 0.18 um CMOS technology. The whole circuit consists of a transimpedance amplifier (TIA), a single-ended to differential amplifier and an output driver. The TIA employs a cascode stage as the input stage and auxiliary amplifier to reduce the miller effect. Current injecting technique is employed to enlarge the input transistor’s transconductance, optimize the noise performance and overcome the lack of voltage headroom. To achieve a wide dynamic range, an automatic gain control circuit with self-adaptive function is proposed. Experiment results show an optical sensitivity of –28 dBm for a bit error rate of 10

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Photodetector resistant to background light noise with extended dynamic range of input signals

Технология и конструирование в электронной аппаратуре ◽

10.15222/tkea2021.3-4.03 ◽

2021 ◽

pp. 3-8

Author(s):

V. M. Lipka ◽

V. V. Ryukhtin ◽

Yu. G. Dobrovolsky

Keyword(s):

Dynamic Range ◽

Automatic Gain Control ◽

Modulation Frequency ◽

Low Frequency ◽

Gain Control ◽

Ambient Air ◽

Frequency Range ◽

Background Light ◽

Useful Signal ◽

Extended Dynamic

Measurement of periodic optical information signals in the background light noise with a photodetector with extended dynamic range is an urgent task of modern electronics and thus has become the aim of this study. To increase the dynamic range of the photodetector, a new version of the automatic gain control (AGC) circuit has been developed, which consists of an AGC controller, an output photodetector amplifier and an AGC detector. The authors measured the dynamic range of the photodetector when receiving optical radiation with a wavelength of 1064 nm in the power range from 2.10–8 to 2.10–5 W at a modulation frequency of 20 kHz with the AGC on. Under these conditions, the dynamic range of the photodetector was found to be up to 67 dB. If the AGC was off, the dynamic range did not exceed 30 dB. Thus, the study made it possible to create a photodetector with an extended dynamic range up to 67 dB based on a new version of the AGC circuit. The design of the photodetector allowed choosing a useful signal of a particular modulation frequency in the frequency range from 3 to 45 kHz and effectively suppresses the frequencies caused by optical interference in the low frequency range from the frequency of the input signal of constant amplitude up to 3 kHz inclusive. This compensates the current up to 15 mA, which is equivalent to the power of light interference of about 15 mW. Further research should address the issues of reliability of the proposed photodetector design and optimization of its optical system. The photodetector can be used in geodesy and ambient air quality monitoring.

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14.85 µW Analog Front-End for Photoplethysmography Acquisition with 142-dBΩ Gain and 64.2-pArms Noise

Sensors ◽

10.3390/s19030512 ◽

2019 ◽

Vol 19 (3) ◽

pp. 512

Author(s):

Binghui Lin ◽

Mohamed Atef ◽

Guoxing Wang

Keyword(s):

Dynamic Range ◽

Automatic Gain Control ◽

Gain Control ◽

Low Noise ◽

Total Power ◽

Cmos Process ◽

Control Block ◽

Silicon Area ◽

Front End ◽

Analog Front End

A low-power, high-gain, and low-noise analog front-end (AFE) for wearable photoplethysmography (PPG) acquisition systems is designed and fabricated in a 0.35 μm CMOS process. A high transimpedance gain of 142 dBΩ and a low input-referred noise of only 64.2 pArms was achieved. A Sub-Hz filter was integrated using a pseudo resistor, resulting in a small silicon area. To mitigate the saturation problem caused by background light (BGL), a BGL cancellation loop and a new simple automatic gain control block are used to enhance the dynamic range and improve the linearity of the AFE. The measurement results show that a DC photocurrent component up-to-10 μA can be rejected and the PPG output swing can reach 1.42 Vpp at THD < 1%. The chip consumes a total power of 14.85 μW using a single 3.3-V power supply. In this work, the small area and efficiently integrated blocks were used to implement the PPG AFE and the silicon area is minimized to 0.8 mm × 0.8 mm.

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Rapid, targeted and culture-free viral infectivity assay in drop-based microfluidics

Lab on a Chip ◽

10.1039/c5lc00556f ◽

2015 ◽

Vol 15 (19) ◽

pp. 3934-3940 ◽

Cited By ~ 34

Author(s):

Ye Tao ◽

Assaf Rotem ◽

Huidan Zhang ◽

Connie B. Chang ◽

Anindita Basu ◽

...

Keyword(s):

High Throughput ◽

Dynamic Range ◽

High Sensitivity ◽

Cost Effective ◽

Serial Dilution ◽

Viral Infectivity ◽

Large Dynamic Range ◽

Infectivity Assay ◽

Dilution Experiments

We developed a rapid, targeted and culture-free infectivity assay using high-throughput drop-based microfluidics. The high sensitivity and large dynamic range of our cost effective assay alleviates the need for serial dilution experiments.

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The Design and Simulation of a New Z-Axis Resonant Micro-Accelerometer Based on Electrostatic Stiffness

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.744.478 ◽

2013 ◽

Vol 744 ◽

pp. 478-483

Author(s):

Bo Yang ◽

Bo Dai ◽

Hui Zhao

Keyword(s):

Dynamic Range ◽

System Simulation ◽

High Sensitivity ◽

Scale Factor ◽

Effective Frequency ◽

Large Dynamic Range ◽

Digital Output ◽

Structure Simulation ◽

Simulation Results ◽

Micro Accelerometer

Resonant micro-accelerometers have good properties such as the large dynamic range, the high sensitivity, the strong anti-interference ability as well as the direct digital output. A new z-axis resonant micro-accelerometer based on electrostatic stiffness is researched. The new z-axis resonant micro-accelerometer consists of a torsional accelerometer and two plane resonators. The sensing movement of the accelerometer is decoupled with oscillation of the plane resonators by electrostatic stiffness, which will benefit to improve the performance of the new z-axis resonant micro-accelerometer. The new structure is designed. The sensitive theory of the acceleration is investigated and the equation of scale factor is deduced under ideal conditions. The simulation is implemented to verify the basic principle by the Ansys and Matlab. The structure simulation results prove that the effective frequency of the torsional accelerometer and the resonator are 0.66kHz and 13.3kHz separately. And the interference modes are isolated with the effective mode apparently. The system simulation results indicate that the scale factor is 37Hz/g and the system has excellent capabilities in locking and tracking natural frequency of resonators, which proves that the basic theory is feasible.

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