Reconfigurable Software Defined Radio Research Articles

A Joint Design of Radar Sensing, Wireless Power Transfer, and Communication Based on Reconfigurable Software Defined Radio

This paper proposes a compact three-mode base station capable of performing radar sensing, communication, and wireless power transfer (WPT) in collaboration with indoor sensor networks. With regard to the wireless sensor node, the base station transmits two-tone signals in the downlink to support its operation and provides two-way communication. The sensor node sends uplink information through backscattering using the third order intermodulation (IM3) product of the rectification. In the radar mode, a single-tone continuous wave (CW) is used to monitor if there is a moving target in the static environment. If a speed is detected, the transmit signal to the node is stopped, while the single-tone CW excitation will continue until the speed of the target is zero, and then the base station transmits a stepped frequency continuous wave (SFCW) signal to measure the distance of the target. The repeat between the two radar waveforms continues until the target is undetectable within the detection range. The software defined radio PlutoSDR is adopted as the base station. The system can wirelessly supply power and bi-directionally communicate with a CO2 sensor node 2 m away. It gives a range resolution of 2.5 cm and a minimum detectable speed of 0.25 m/s in the radar mode.

Error correction and uncertainty measurement of short-open-load calibration standards on a new concept of software defined instrumentation for microwave network analysis

Software-Defined Radio (SDR) has appeared as a sufficient framework for the development and testing of the measurement systems such as a signal generator, signal analyzer, and network analysis used in the network analyzer. However, most of researchers or scientists still rely on commercial analyzers were larger benchtop instruments, highly cost investment and minimum software intervention. In this paper, a new concepts measurement revolution called as Software Defined Instrumentation (SDI) on network analysis is presented, which is based on reconfigurable SDR, a low-cost implementation, ability to access RF chain and utilizing open source signal processing framework. As a result, a Vector Network Analyzer (VNA) has been successful implemented by deploying an SDR platform, test sets, and data acquisition from the GNU Radio software in host PC. The known calibration process on SHORT-OPEN-LOAD (SOL) technique is validated to ensure measurement data from this SDI free from systematic error. Two types of SOL calibration standards used for a comparison study to validate the SDI measurement system which is capable of generating the response on the differential of standard quality and accuracy of standards kits. Finally, calibration uncertainty analysis is also presented in this work by utilizing RF open source package without any cost addition.

Design of Reconfigurable SDR Platform for Antenna Selection Aided MIMO Communication System

In recent years, antenna selection (AS) has become one of the most popular research topics for massive multiple-input multiple-output (MIMO) system due to its capability of reducing the number of radio frequency chains utilized for MIMO communications, while remaining the MIMO advantages, such as increased bandwidth efficiency and reliability. In this paper, an efficient norm-based AS (NBAS) algorithm is investigated and implemented in the software defined radio (SDR) MIMO communication platform, which consists of field-programmable gate arrays (FPGAs). Owing to the high freedom and fast reconfigurable FPGA hardware, the SDR MIMO communication platform is capable of developing prototype of NBAS-aided MIMO system. More specifically, the implemented NBAS aided SDR MIMO system is capable of achieving uplink communication from users to the base station via time division duplex (TDD). A time-varying fading channel generation model is designed for SDR MIMO platform to enrich our experimental results. Additionally, a novel multiplexer (MUX) circuit module is designed and implemented to enhance the hardware performance of the FPGA in term of delay and resource usage. More specifically, the Results show that by implementing the low-complexity NBAS, the channel capacity performance of the SDR MIMO system may be significantly improved by around 15%. It is also showed that our proposed optimized MUX circuit intellectual property may reduce the critical path delay by about 2:16 ns, and save at lease 3% hardware resources in SDR FPGA.

Low complexity reconfigurable channelizers using non-uniform filter banks

A Software Defined Radio (SDR) channelizer needs reconfigurable sharp filter banks with low implementation complexity. In this paper, the design of non-uniform Modified Discrete Fourier Transform filter bank (MDFT FB) is proposed to be used in SDR channelizer. The frequency response masking technique is used to design the prototype filter which gives sharp filters with lower hardware complexity, compared to the finite impulse response filters. The canonic signed digit (CSD) representation is used in the design, to convert the continuous filter coefficients into discrete coefficients. Multi-objective artificial bee colony algorithm is utilized to improve the performance degradation when the CSD represented filter coefficients are used. Further, the shift inclusive differential technique with common sub-expression elimination is used to reduce the number of adders. Xilinx ISE is used to verify the hardware requirement, for the implementation of the non-uniform MDFT FB. Hence low complexity reconfigurable SDR channelizers using non-uniform MDFT FB is proposed in this paper.

GRT

The importance of software-defined radio (SDR) continues to increase. However, existing SDR platforms become less efficient as the wireless industry moves towards Gigabit WiFi. In this work, we propose a novel reconfigurable SDR platform named GRT. With the help of reconfigurable architecture and corresponding software support, SDR designs on GRT can leverage high performance of the underlying hardware and provide sufficient usability, including the support for efficient modular design, commodity interface, good programmability, code reusability, etc. We implement an 802.11a/g WiFi system on GRT to evaluate its performance. The results demonstrate that GRT can achieve a substantial improvement in usability while still satisfying the performance requirement.

Algorithm Driven System Selection with Reconfigurable Software Defined Radio in Mobile Devices

Emerging global standards for high-speed data, like WiMAX, WiBro, HSDPA and EVDO, presently provide islands of coverage. Such standards require new capabilities from mobile devices. With the coexistence of independent standards, protocols and services it is essential to develop wireless platform that can seamlessly connect to any access networks supported by different standards. Here proposed system architecture supports SDR among multiple communication standards. A logical interface between SDR subsystem and higher level protocol called system reconfiguration manager acts as a logical interface between SDR subsystem and user/application layer. Designed algorithm in SCM enables the proper selection of communication system e.g. OFDM, UMTS etc. and triggers for handover from one communication system to another when user/application specified requirements met by SDR subsystem.