Device verification tests for high speed analog to digital converters used in satellite communication systems

2007 ◽  
Author(s):  
Seokjin Kim ◽  
Radmil Elkis ◽  
Martin M. Peckerar
Keyword(s):  
Communication Systems ◽  
High Speed ◽  
Satellite Communication ◽  
Analog To Digital Converters ◽  
Analog To Digital

scholarly journals An Improved All-Digital Background Calibration Technique for Channel Mismatches in High Speed Time-Interleaved Analog-to-Digital Converters

Electronics ◽  
2020 ◽  
Vol 9 (1) ◽  
pp. 73
Author(s):  
Van-Thanh Ta ◽  
Van-Phuc Hoang ◽  
Van-Phu Pham ◽  
Cong-Kha Pham
Keyword(s):  
Communication Systems ◽  
High Speed ◽  
Dynamic Range ◽  
Analog To Digital Converters ◽  
Background Calibration ◽  
Calibration Technique ◽  
Analog To Digital ◽  
Digital Background Calibration ◽  
Field Programmable ◽  
Time Interleaved

The time-interleaved analog-to-digital converters (TIADCs), performance is seriously affected by channel mismatches, especially for the applications in the next-generation communication systems. This work presents an improved all-digital background calibration technique for TIADCs by combining the Hadamard transform for calibrating gain and timing mismatches and averaging for offset mismatch cancellation. The numerical simulation results show that the proposed calibration technique completely suppresses the spurious images due to the channel mismatches at the output spectrum, which increases the spurious-free dynamic range (SFDR) and signal-to-noise and distortion ratio (SNDR) by 74 dB and 43.7 dB, respectively. Furthermore, the hardware co-simulation on the field programmable gate array (FPGA) platform is performed to confirm the effectiveness of the proposed calibration technique. The simulation and experimental results clarify the improvement of the proposed calibration technique in the TIADC’s performance.

INNOVATIVE METHOD OF SATELLITE COMMUNICATION

2019 ◽  
Author(s):  
Teodor Narytnik ◽  
Vladimir Saiko
Keyword(s):  
Communication Systems ◽  
High Speed ◽  
Satellite Communication ◽  
Radio Channel ◽  
Satellite Communications ◽  
Service Area ◽  
Satellite Systems ◽  
Orbit Satellite ◽  
Geometric Size ◽  
Distributed Satellite

The technical aspects of the main promising projects in the segments of medium and low-orbit satellite communication systems are considered, as well as the project of the domestic low-orbit information and telecommunications system using the terahertz range, which is based on the use of satellite platforms of the micro- and nanosatellite class and the distribution of functional blocks of complex satellite payloads more high-end on multiple functionally related satellites. The proposed system of low-orbit satellite communications represents the groupings of low-orbit spacecraft (LEO-system) with the architecture of a "distributed satellite", which include the groupings of the root (leading) satellites and satellite repeaters (slaves). Root satellites are interconnected in a ring network by high-speed links between the satellites. The geometric size of the “distributed satellite” is the area around the root satellite with a radius of about 1 km. The combination of beams, which are formed by the repeater satellites, make up the service area of the LEO system. The requirements for the integrated service area of the LEO system (geographical service area) determine the requirements for the number of distributed satellites in the system as a whole. In the proposed system to reduce mutual interference between the grouping of the root (leading) satellites and repeater satellites (slaves) and, accordingly, minimizing distortions of the information signal when implementing inter-satellite communication, this line (radio channel) was created in an unlicensed frequency (e.g., in the terahertz 140 GHz) range. In addition, it additionally allows you to minimize the size of the antennas of such a broadband channel and simplify the operation of these satellite systems.

MATHEMATICAL MODEL OF THE RADIATING APERTURE OF HEADLIGHTS CONSISTING OF SEGMENT-PARABOLIC ANTENNAS

2021 ◽  
pp. 69-78
Author(s):  
Ю.Г. Пастернак ◽  
В.А. Пендюрин ◽  
К.С. Сафонов
Keyword(s):  
Mathematical Model ◽  
Antenna Arrays ◽  
Communication Systems ◽  
High Speed ◽  
Satellite Communication ◽  
The Arctic ◽  
Northern Latitudes ◽  
Electronic Model ◽  
Mobile Satellite ◽  
High Orbit

Решение задачи связи в Арктике, а также в тундре, в тайге, в лесу, в море, на полях возможно только с использованием мобильных систем спутниковой связи. ФГУП «Космическая связь» (г. Москва) располагает группировкой спутников, которая постоянно расширяется. Для надежной связи в Арктике и в северных широтах, помимо геостационарных спутников, запущены спутники, движущиеся по высокоорбитальным траекториям. Для переключения со спутника на спутник, входящий в зону видимости абонента, необходимо использовать антенные решетки. Проблема заключается в том, что в настоящее время отсутствуют мобильные терминалы высокоскоростной спутниковой связи, а стоимость зарубежных аналогов препятствует широкому их использованию (достигает 50 тысяч долларов). Обычно радиолокационная связь (РЛС) с фазированной антенной решеткой используется для наблюдения за тысячами угловых точек, для отслеживания сотни целей. Такие требования могут быть выполнены только путем сканирования луча в пространстве в течение микросекунды. Ясно, что необходимо электронное управление лучом, поскольку механически вращать антенну не представляется возможным. Лишь некоторая часть вышеуказанных проблем будет затрагиваться в этой статье, ниже будут представлены электронная модель антенной решетки и её математическая модель The solution of the communication problem in the Arctic, as well as in the tundra, in the taiga, in the forest, in the sea, in the fields is possible only with the use of mobile satellite communication systems. FSUE "Space Communications" (Moscow) has a constantly expanding group of satellites. For reliable communication in the Arctic and Northern latitudes, in addition to geostationary satellites, satellites moving along high-orbit trajectories were launched. To switch from one satellite to the other included in the subscriber's visibility area, it is necessary to use antenna arrays. The problem is that currently there are no mobile terminals for high-speed satellite communication, and the cost of foreign analogues prevents their widespread use (up to 50 thousand dollars). Typically, a phased array radar is used to track thousands of corner points to track hundreds of targets. Such requirements can only be met by scanning the beam in space for a microsecond. It is clear, that electronic beam control is necessary since it is not possible to mechanically rotate the antenna. Only some of the above problems will be touched upon in this article. An electronic model of the antenna array and its mathematical model is presented

scholarly journals RF-MEMS Monolithic K and Ka Band Multi-State Phase Shifters as Building Blocks for 5G and Internet of Things (IoT) Applications

Sensors ◽  
2020 ◽  
Vol 20 (9) ◽  
pp. 2612 ◽  
Author(s):  
Jacopo Iannacci ◽  
Giuseppe Resta ◽  
Alvise Bagolini ◽  
Flavio Giacomozzi ◽  
Elena Bochkova ◽  
...  
Keyword(s):  
Internet Of Things ◽  
Communication Systems ◽  
High Speed ◽  
Phase Shifter ◽  
Satellite Communication ◽  
Rf Mems ◽  
Building Blocks ◽  
Phase Shifters ◽  
Small Cells ◽  
Mems Technology

RF-MEMS, i.e., Micro-Electro-Mechanical Systems (MEMS) for Radio Frequency (RF) passive components, exhibit interesting characteristics for the upcoming 5G and Internet of Things (IoT) scenarios, in which reconfigurable broadband and frequency-agile devices, like high-order switching units, tunable filters, multi-state attenuators, and phase shifters will be necessary to enable mm-Wave services, small cells, and advanced beamforming. In particular, satellite communication systems providing high-speed Internet connectivity utilize the K and Ka bands, which offer larger bandwidth compared to lower frequencies. This paper focuses on two design concepts of multi-state phase shifter designed and manufactured in RF-MEMS technology. The networks feature 4 switchable stages (16 states) and are developed for the K and Ka bands. The proposed phase shifters are realized in a surface micromachining RF-MEMS technology and the experimentally measured parameters are compared with Finite Element Method (FEM) multi-physical electromechanical and RF simulations. The simulated phase shifts at both the operating bands fit well the measured value, despite the measured losses (S21) are larger than 5–7 dB if compared to simulations. However, such a non-ideality has a technological motivation that is explained in the paper and that will be fixed in the manufacturing of future devices.

Design of Robust Quantizers for Low-Bit Analog-to-Digital Converters for Gaussian Source

2019 ◽  
Vol 28 (supp01) ◽  
pp. 1940002 ◽  
Author(s):  
Milan R. Dinčić ◽  
Zoran H. Perić ◽  
Dragan B. Denić ◽  
Zoran Stamenković
Keyword(s):  
Energy Consumption ◽  
Communication Systems ◽  
Mimo Systems ◽  
Automatic Gain Control ◽  
Gain Control ◽  
Analog To Digital Converters ◽  
Signal Power ◽  
Analog To Digital ◽  
Wide Range ◽  
Gaussian Source

This paper considers the design of robust logarithmic [Formula: see text]-law companding quantizers for the use in analog-to-digital converters (ADCs) in communication system receivers. The quantizers are designed for signals with the Gaussian distribution, since signals at the receivers of communication systems can be very well modeled by this type of distribution. Furthermore, linearization of the logarithmic [Formula: see text]-law companding function is performed to simplify hardware implementation of the quantizers. In order to reduce energy consumption, low-resolution quantizers are considered (up to 5 bits per sample). The main advantage of these quantizers is high robustness — they can provide approximately constant SNR in a wide range of signal power (this is very important since the signal power at receivers can vary in wide range, due to fading and other transmission effects). Using the logarithmic [Formula: see text]-law companding quantizers there is no need for using automatic gain control (AGC), which reduces the implementation complexity and increases the speed of the ADCs due to the absence of AGC delay. Numerical results show that the proposed model achieves good performances, better than a uniform quantizer, especially in a wide range of signal power. The proposed low-bit ADCs can be used in MIMO and 5G massive MIMO systems, where due to very high operating frequencies and a large number of receiving channels (and consequently a large number of ADCs), the reduction of ADC complexity and energy consumption becomes a significant goal.

Sign in / Sign up

Export Citation Format

Share Document