Universal Software Radio Peripheral Hardware Research Articles

Prototipo de red GSM basada en SDR

This paper presents the implementation of a GSM (Global System for Mobile Communications) network prototype based on SDR (Software Defined Radio) using the Linux-based OpenBTS software and the USRP (Universal Software Radio Peripheral) hardware. GSM has been chosen because it is one of the most successful standards with the most significant impact on the mobile telephony ecosystem. It has been the key to the development of subsequent generations. By integrating GSM with SDR, it is possible to implement a prototype of an experimental GSM network, which can become a testbed for future innovations and developments in SDR dynamics that seek to provide alternative mobile infrastructures to rural populations in Ecuador and around the word that they still are part of the great digital divide.

Experimentations on the Transmit Power of a Universal Software Radio Peripheral Using GNU Radio Framework and a Handheld RF Explorer

The Universal Software Radio Peripheral (USRP) and GNU Radio framework have a wide range of applications and are actively in use for teaching, research and for practical deployment of various trending wireless technologies. In this work, we explore the relationships between the power outputs of a USRP B200 device and its operating frequencies and USRP Hardware Driver (UHD) gains. These relationships are not precisely specified on the device datasheet, thereby hindering prompt design and experimentation decisions among Software Defined and Cognitive Radio (SDCR) researchers. A general purpose handheld spectrum analyser was engaged for recording the power outputs from the USRP B200 device within an experimental testbed that was setup for this study. The B200 device was driven by a GNU radio flowgraph designed for both wired and wireless modes and running on a general purpose host computer in the testbed. The results indicate that the output power decreases while the centre frequency increases, whereas the output power increases as the UHD gain increases from 65 dB until the device reaches the saturation point at 89.9 dB. These results provide a handy toolkit for SDCR researchers and practitioners.

Integrating Software Defined Radio with USRP

The USRP1 is the original Universal Software Radio Peripheral hardware (USRP) that provides entry-level RF processing capability. Its primary purpose is to provide flexible software defined radio development capability at a low price. You can control the frequency you receive and transmit by installing different daughter-boards. The authors' USRP model had been configured to receive a signal from local radio stations in the DC, Maryland metropolitan area with the BasicRX model daughterboard. The programmable USRP was running python block code implemented in the GNU Radio Companion (GRC) on Ubuntu OS. With proper parameters and sinks the authors were able to tune into the radio signal, record the signal and extract the in-phase (I) and quadrature phase (Q) data and plot the phase and magnitude of the signal. Using the terminal along with proper MATLAB and Octave code, they were able to read the I/Q data and look at the Fast Fourier Transform (FFT) plot along with the I/Q data. With the proper equations, you could determine not only the direction of arrival, but one would also be able to calculate the distance from the receiver to the exact location where the signal is being transmitted. The purpose of doing this experiment was to gain experience in signal processing and receive hands on experience with the USRP and potentially add a tracking system to the authors' model for further experiments.

Implementation of a genetic algorithm-based decision making framework for opportunistic radio

The cognitive radio (CR) is known as a radio that can reconfigure its transceiver parameters based on the environmental awareness. The opportunistic radio (OR) is considered in this work, with a narrower definition where the awareness is limited to the spectrum knowledge. The decision making framework is employed as a crucial entity to control the behaviour of the OR. The main purpose is to enable an efficient spectrum usage while avoiding the interference to other users. This study describes the proposed OR decision making framework including the flow of context information as an input process to the decision making engine, the context filtering and the reasoning mechanisms in which the decision optimisation is achieved using a genetic algorithm (GA)-based approach. The system stability of the GA-based reasoning engine is tested through simulations. Then, the experimental study is performed on a test platform for a practical proof of the concept. The test platform is based on the Ettus USRP (Universal Software Radio Peripheral) hardware and the GNU Radio open source software. Several tests were carried out to observe the OR capabilities of the proposed decision making framework. Test environment settings together with the observation results are provided in this study, covering the spectrum sensing and opportunistic channel allocation in the industrial, scientific and medical (ISM) band of 2.4 GHz.