Multi-channel data compression

Digital phased array antennas (DPAAs) have been widely used in modern radar systems. The flexible production and testing of large-scale DPAAs are becoming a hot research topic. The dedicated calibration elements are passive because they do not have transmitter and receiver modules. These elements cannot be used to test DPAAs. In this paper, we design a multichannel automatic test and data acquisition system for DPAAs. Our motivation is to use the system to verify the correctness and stability of an entire DPAA. The system can achieve snapshot data acquisition of 1152 optical fibers, and it can also process echo data in real time by digital beam forming (DBF) and record the processing results. At present, the system has been put into production for testing of large-scale DPAAs, and it can test the DPAA flexibly and steadily.

Telemetric information is great in size, requiring extra room and transmission time. There is a significant obstruction of storing or sending telemetric information. Lossless data compression (LDC) algorithms have evolved to process telemetric data effectively and efficiently with a high compression ratio and a short processing time. Telemetric information can be packed to control the extra room and association data transmission. In spite of the fact that different examinations on the pressure of telemetric information have been conducted, the idea of telemetric information makes pressure incredibly troublesome. The purpose of this study is to offer a subsampled and balanced recurrent neural lossless data compression (SB-RNLDC) approach for increasing the compression rate while decreasing the compression time. This is accomplished through the development of two models: one for subsampled averaged telemetry data preprocessing and another for BRN-LDC. Subsampling and averaging are conducted at the preprocessing stage using an adjustable sampling factor. A balanced compression interval (BCI) is used to encode the data depending on the probability measurement during the LDC stage. The aim of this research work is to compare differential compression techniques directly. The final output demonstrates that the balancing-based LDC can reduce compression time and finally improve dependability. The final experimental results show that the model proposed can enhance the computing capabilities in data compression compared to the existing methodologies.

Aiming at a multi-channel data acquisition and transmission system based on FPGA, the design scheme, functional circuit and logic design method of the system are introduced in detail. The system uses FPGA as the control core to control TLC2543 analog-to-digital converter and complete the circulation acquisition of 11-channel analog data. The transmission end uses Ethernet chip RTL8201 to communicate with the upper computer, which can monitor the data changes of each channel. The correctness of each function module is verified by software simulation. The design can meet the requirements of multi-channel signal acquisition and transmission.

Meteorological radiosondes are launched routinely to obtain lower troposphere soundings of temperature, relative humidity, pressure, and wind parameters. The ability to carry extra sensors considerably extends the usefulness and cost-effectiveness of each sounding, permitting research into other properties of the lower atmosphere such as ozone, radioactivity, and electric field. An inexpensive four-channel digital data acquisition system is described which fits within the Vaisala RS80-15L radiosonde, for integration with other sensors. Using a 12-bit analog to digital conversion, a microcontroller formats the voltage measurements obtained for serial transmission over the radiosonde’s UHF radio link at 300baud. Maximum sampling rate on one channel is 10Hz, which is reduced if multiple channels are sampled. The standard meteorological data telemetry is unaffected. During an entire flight in which the equipment experienced atmospheric temperatures from 4°Cto−55°C, the absolute error on a 5V fsd range was less than 15mV.

A computer-based data acquisition and analysis system was developed customized to EMG measurement and analysis requirements. The system was designed as an assistive tool for researchers studying human electrophysiology and kinesiology. A user-friendly interface characterized by a great adaptability and compatibility with other similar existing software packages was implemented, enabling multichannel acquisition, data storage and analysis. The application integrates the most frequent processing techniques required by EMG researchers and analysts, as well as a number of advanced signal processing techniques adjusted to the features of the EMG signal. The system comprises flexible signal analysis and display modules, forming a fully operational tool that can be easily configured to serve any similar purposed measurement requirements.

This paper describes the architecture and implementation of the Data Compression Chip (DCC) for high-performance lossless data compression for multi-channel highspeed data networking applications. The DCC implements an improved adaptive string matching algorithm using a new parallel architecture-the Variable Length String Matcher (VLSM). The VLSM quickly performs an otherwise time-intensive string-matching procedure. Furthermore, by avoiding the typical data structures that require very large and fast memory to store a compression vocabulary, the DCC's VLSM minimizes system costs. By maintaining separate vocabularies for multiple channels, the DCC eliminates the loss of compression efficiency otherwise experienced in typical frame-multiplexed or reset-at-frame applications. The DCC uses a high-performance algorithm with a custom parallel architecture to minimize vocabulary memory (VRAM) requirements and provide very high throughput and compression efficiency for multiple channels. The device has been realized in 0.8 micron CMOS technology with a die area of 9.27 mm/spl times/10.0 mm and power dissipation about 1 W at 20 MHz. It employs a 160 pin PQFP package. >

The paper designed a multi-channel data acquisition system based on PXI 6281. It used DAQmx technology in LabVIEW for synchronous analog channel data acquisition. It realized multi-channel real-time data acquisition, processing, display and data auto-saving. Data acquisition system consists of three major modules: the pressure measurement module, the motor speed measurement modules and real-time temperature measurement module. It has advantage of short cycle of technological upgrading, development and low maintenance costs. It has some reference value for other data acquisitions.

In order to optimise maintenance and increase safety, the Royal Netherlands Navy initiated the development of a multi-channel on-board data acquisition system for its Lynx helicopters. This AIDA (Automatic In-flight Data Acquisition) system records usage and loads data on main rotor, engines and airframe. We used refinement in combination with model checking to arrive at a formally verified prototype implementation of the AIDA system, starting from the functional requirements.

Electromagnetic launching system is composed of the Electromagnetic Railgun (EMRG) and the large-scale Pulse Power System (PPS). According to the different test requirements of PPS and EMRG, the special master-slave distributed data acquisition software for electromagnetic launching system is designed by using LabVIEW graphic language. The test host and the sub-machines are multi-channel transient data acquisition systems based on PXI bus. The host PXI is used to measure the comprehensive parameters of the EMRG in multi-physical field. All sub-PXIs are used to diagnose the discharge current signals of each Pulse Forming Unit (PFU). The database management software uses C# programming language to design a friendly human-computer interaction interface, and uses SQL Server software to establish and manage the database, which realizes the comprehensive management of experimental data, tasks and resources involved in the EMRG experiments. The experimental information and experimental data are classified and filed, and the experimental data can be queried, and the experimental results can be analyzed and compared. The data acquisition and experimental database management software has perfect functions, friendly user interface, convenient operation, good versatility, and can also be used in other experimental occasions.

Squeezed branch piles, which boast the advantages of great bearing capacity, small settlement, and good stability, are an important infrastructure in the foundation of buildings, and their safety state is related to the safety of the entire structure. As a non-destructive testing method, surface potential can be used to effectively evaluate the damaged state of a pile foundation without destroying its stability. On this basis, in this study, the characteristics of surface potential change during settlement and deformation of squeezed branch piles under graded loading were tested and analyzed with the aid of a self-made loading system of reaction beams and an LB-IV multi-channel potential data acquisition system. The results show that: Under graded loading, squeezed branch piles can produce surface potential signals whose intensity can well reflect the settlement and local failure characteristics of the pile foundation; The potential signals change in advance of load; and they fluctuate violently before local fracturing of squeezed branch piles. The unstable fluctuation of the potential signal can be regarded as a precursor to the fracturing of squeezed branch piles. The research results have positive theoretical significance and important application value for assessing the stability of both branch piles and their stress states on site and monitoring and forecasting the disaster of pile foundation instability.

Many Industries motivated to achieve smart ways to monitor and acquire plant parameters and control plant actuators remotely. A wireless data acquisition and control system can be used for realizing smart automation. Different technologies are used to transmit the sensor data wirelessly to remote data acquisition system. Bluetooth and ZigBee technologies are the widely used short term wireless technology. In Bluetooth technology, data can be sent wirelessly to remote location, with limited range and data transfer rate. In Bluetooth 5.0, the distance is 50-60 meters and the data transfer speeds of upto 5-10Mbps. Data transmission with ZigBee based network is also limited to its range and data transfer rate. The maximum range is approx. 70-100 meter and a maximum data transfer rate of 250Kbps. In order to overcome the limitations such as short range and lower data rate, a Wi-Fi based sensor network is proposed. i.e. the sensor data is transmitted to the internet server through Message Queuing Telemetry Transport (MQTT) protocol. To realize the system, different sensors are used and the sensor output is digitized through external Analog to Digital Converter ADS1115. I2C communication bus is used to establish communication between ADS1115 and NodeMCU. The Node-RED graphical programming tool is used to develop data acquisition and control software. This paper aims to change the inflexibility of wired system and develop a Real-time, High-speed, Multi-channel Wireless Data Acquisition and Control System. The proposed system is suitable for access Real-time data in anywhere in the world through MQTT server. Automatic/Manual control signal also can be generated from anywhere to actuate the load remotely.

This paper describes a high-speed data acquisition and transmission system for millimeter-wave imaging based on optical fibre and PCIe interfaces, which includes a multi-channel analog-to-digital conversion module, a data transmission module, and a data reception module. The scheme can circumvent the inherent shortcomings of bulky volume, poor reliability, and inability of large-scale expansion of array channels caused by the multi-channel data transmission system using multi-strand SMA cables, and has the advantages of small volume, light weight, fast data transmission rate, and easy to upgrade the performance, etc. It can be widely applied to the multi-channel data acquisition and transmission system, and has a broad application prospect in the field of array imaging radar and sonar imaging.

The volume of telemetry data is gradually increasing, both because of the increasingly larger number of parameters involved, and the use of higher sampling frequencies. Efficient data compression schemes are therefore needed in space telemetry systems to improve transmission efficiency and reduce the burden of required spacecraft resources, in particular regarding their transmitter power. In our primary study, a D-CLU algorithm was proposed to perform lossless compression for telemetry data, and achieve better performance. However, a limitation of this algorithm is that the compression time may become longer when the clustering head (CH) and outlier (which are compressed by LZW algorithm) numbers increase. To reduce compression delay, this paper proposed a modified character string (MCS) parallel search strategy for LZW algorithm (denoted by MCS-based LZW). The proposed MCS-based LZW algorithm designs coding principle, dictionary update rule and search strategy according to the character string matching results. Example verification and simulation results show that the proposed algorithm can effectively decrease the dictionary search times, and thus reduce the compression time.

In order to meet the tomato color sorting system with the requirements of multi-channel data acquisition and real-time processing, [ ]firstly, a multi-channel color digital acquisition and processing technique program based on FPGA were proposed . Then, a multi-channel data acquisition and real-time parallel processing system was built. The RGB color sensors were slected as detection components and the FPGA chip EP1C3T144C8 was slected as a core of data acquisition and processing. Meanwhile, ports of signal acquisition and the solenoid valve control were adopted a two-way analog switch HC4051 for saving I/O ports of FPGA. Thirdly, under the modular design and module reuse principles, we developed all modules with VHDL Language in QuartusII development environment. Finally, RTL and time sequence simulation for the system were done. The results showed that the connections between the modules accord with control logics. [²»´o¶O accorded ¹ýE¥E½] The performance of system time sequencev are good, which can meet with the requirements of real-time processing of tomato color sorting. On these bases, we also conducted a tomato sorting test verification. The results showed that the average accuracy of sorting is 98.70% and coefficient of variation is 0.01. This results can meet requirements of production.

Summary form only given. We propose a novel compression method, static PPM (SP), which supports partial decode (p-decode) with low memory and computation requirement. P-decode is a function that decodes data from an arbitrary position without decoding the whole, which is critical for exploiting large data in a compressed state. While conventional compression methods do not support p-decode, recent self-indexing data structures, such as compressed suffix arrays (CSA) (Sadakane, K., J. Algorithms, vol.48, no.2, p.294-313, 2003) and FM-index (Ferragina, P. and Manzini, G. Proc. ACM-SIAM SODA, p.269-78, 2001), support p-decode. However, they have to store the whole compressed data in memory, since the order of the data is not preserved after compression. This causes a serious problem when the compressed data is larger than memory size. In contrast, SP does not have to store compressed data in memory and, thus, is the first compression method that supports p-decode for very large compressed data. In order to show SP's high compression performance inherited from PPM and its p-decode performance, we compared SP, CSA, FM-index, gzip (with option -9) and bzip (with option -9) in terms of speed and compression ratio. The results show that SP achieves fast p-decode with high compression ratio.