The Impact of RF-Impairments and Automatic Gain Control on UMTS-HSDPA-Throughput Performance

Impact of Signal Quantization on the Performance of RFI Mitigation Algorithms

Remote Sensing ◽

10.3390/rs11172023 ◽

2019 ◽

Vol 11 (17) ◽

pp. 2023 ◽

Cited By ~ 2

Author(s):

Raúl Díez-García ◽

Adriano Camps

Keyword(s):

Automatic Gain Control ◽

Gain Control ◽

Earth Observation ◽

Signal Quantization ◽

Time Frequency ◽

Spatial Coverage ◽

Mitigation Methods ◽

Frequency Properties ◽

The Impact ◽

Important Design

Radio Frequency Interference (RFI) is currently a major problem in Communications and Earth Observation, but it is even more dramatic in Microwave Radiometry because of the low power levels of the received signals. Its impact has been attested in several Earth Observation missions. On-board mitigation systems are becoming a requirement to detect and remove affected measurements, increasing thus radiometric accuracy and spatial coverage. However, RFI mitigation methods have not been tested yet in the context of some particular radiometer topologies, which rely on the use of coarsely quantized streams of data. In this study, the impact of quantization and sampling in the performance of several known RFI mitigation algorithms is studied under different conditions. It will be demonstrated that in the presence of clipping, quantization changes fundamentally the time-frequency properties of the contaminated signal, strongly impairing the performance of most mitigation methods. Important design considerations are derived from this analysis that must be taken into account when defining the architecture of future instruments. In particular, the use of Automatic Gain Control (AGC) systems is proposed, and its limitations are discussed.

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Research on Measurement Method of Ultrasonic Transit Time based on Automatic Gain Control

2020 39th Chinese Control Conference (CCC) ◽

10.23919/ccc50068.2020.9188416 ◽

2020 ◽

Author(s):

Qinyong Ma ◽

Yuanzheng Zhang

Keyword(s):

Transit Time ◽

Measurement Method ◽

Automatic Gain Control ◽

Gain Control

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Diverging Paths

10.1093/oso/9780198779599.003.0012 ◽

2018 ◽

Author(s):

Dirk Luyten

Keyword(s):

World War Ii ◽

Welfare State ◽

Social Protection ◽

National Level ◽

Gain Control ◽

Political Strategy ◽

State Development ◽

Social Reforms ◽

Welfare State Development ◽

The Impact

For the Netherlands and Belgium in the twentieth century, occupation is a key concept to understand the impact of the war on welfare state development. The occupation shifted the balance of power between domestic social forces: this was more decisive for welfare state development than the action of the occupier in itself. War and occupation did not result exclusively in more cooperation between social classes: some interest groups saw the war as a window of opportunity to develop strategies resulting in more social conflict. Class cooperation was often part of a political strategy to gain control over social groups or to legitimate social reforms. The world wars changed the scale of organization of social protection, from the local to the national level: after World War II social policy became a mission for the national state. For both countries, war endings had more lasting effects for welfare state development than the occupation itself.

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Measuring Current in a Power Converter Using Fuzzy Automatic Gain Control

Applied Sciences ◽

10.3390/app11135793 ◽

2021 ◽

Vol 11 (13) ◽

pp. 5793

Author(s):

Bartosz Dominikowski

Keyword(s):

High Resolution ◽

Fuzzy Controller ◽

Automatic Gain Control ◽

Gain Control ◽

Measurement Range ◽

Power Converter ◽

Current Measurement ◽

Dc Power ◽

Programmable Gain ◽

Electric Loads

The accuracy of current measurements can be increased by appropriate amplification of the signal to within the measurement range. Accurate current measurement is important for energy monitoring and in power converter control systems. Resistance and inductive current transducers are used to measure the major current in AC/DC power converters. The output value of the current transducer depends on the load motor, and changes across the whole measurement range. Modern current measurement circuits are equipped with operational amplifiers with constant or programmable gain. These circuits are not able to measure small input currents with high resolution. This article proposes a precise loop gain system that can be implemented with various algorithms. Computer analysis of various automatic gain control (AGC) systems proved the effectiveness of the Mamdani controller, which was implemented in an MCU (microprocessor). The proposed fuzzy controller continuously determines the value of the conversion factor. The system also enables high resolution measurements of the current emitted from small electric loads (≥1 A) when the electric motor is stationary.

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