Introduction of USRP and Demos by Dong Han & Rui Zhu
Introduction USRP(Universal Software Radio Peripheral ): A computer-hosted software radio, which is commonly used by research labs, universities. Motherboard + Daughterboard
Introduction USRP(Universal Software Radio Peripheral ): A RF frontend, FPGA and an OMAP 3, which includes an ARM processor and a DSP. This allows standalone operation for embedded applications. A modular design allows the USRP E100 to operate from DC to 6 GHz.
Daughterboard: WBX 50-2200 MHz Rx/Tx The WBX is a wide bandwidth transceiver. It is ideal for applications requiring access to a number of different bands within its range - 50 MHz to 2.2 GHz. Example application areas: land-mobile communications, maritime and aviation band radios; cell phone base stations, PCS and GSM multi-band radios; wireless sensor networks; broadcast TV.
The USRP hardware driver (UHD) The USRP hardware driver (UHD) is the device driver for use with the USRP product family. Support : Linux, MacOS, and Windows platforms. Several frameworks including GNU Radio, LabVIEW and Simulink use UHD.
Software frameworks that support UHD GNU Radio GNU Radio is an open source toolkit that can be used to develop software-defined radios. This framework uses a combination of C++ and Python to optimize DSP performance while providing an easyto-use application programming environment. LabVIEW MATLAB and Simulink Custom and/or proprietary frameworks
Dome 1
Background Demo 1- FM Receiver FM stands for frequency modulation, which is the process of encoding a message signal, such as music, in the frequency of an RF signal. Broadcast FM radio around the world is typically transmitted using center frequencies from 87.5 MHz to 108 MHz, and each station is generally allocated a bandwidth of 200 khz. For this example, use the center frequency of 106.7 MHz, the known location of a local radio station near the center of the US FM band.
Demo 1- FM Receiver
Demo 1- FM Receiver
Demo 2
Demo 2 - GSM Base station Background ---- GSM (Global System for Mobile Communications), is a standard set developed by the European Telecommunications Standards Institute (ETSI) to describe protocols for second generation (2G) digital cellular networks used by mobile phones. ---- The base station contains the equipment for transmitting and receiving signals (transceivers), antennas, and equipment for encrypting and decrypting communications with the base station controller (BSC).
Demo 2 - GSM Base station Structure of the mobile phone cellular network
Demo 2 - GSM Base station OpenBTS (Open Base Transceiver Station) ---OpenBTS is a software-based GSM access point, allowing standard GSM-compatible mobile phones to be used. ---This project uses the USRP to present a GSM air interface to a standard GSM handset. It s an open-source Unix application.
Demo 2 - GSM Base station Hardware
Demo 2 - GSM Base station OpenBTS: modulation and demodulation. Assign a channel for every communication. Asterisk: play the roles of MSC. If two communicators are in the same OpenBTS network, build the communication links. Otherwise, access the VoIP gateway to connect to the PSTN. MySQL: Replace the HLR( Home Location Register)and the VLR(Visitor Location Register)
Demo 2 - GSM Base station
Demo 2 - GSM Base station Official website of OpenBTS http://wush.net/trac/rangepublic
Demo 3
Demo 3- Simulation of Wireless Background Outlet Controller A wireless outlet is controlled remotely by a controller. The controller uses 315 MHz carrier signal sending information to outlet. Our aim and method Our aim is to use USRP to control a remote outlet, that is to simulate a real controller. We try to use USRP to sniff the signal. Then we analysis the signal and use USRP to replay it.
Signal Collection (1) Generally, to simulate the behavior of controller, to get the signal that controls an outlet. We have two method. One is to get signal from microcontroller. We can use oscilloscope to get signal sequence, which is composed by high voltage and low level voltage to define 1 and 0, respectively. The second method is that we can sense the signature in air by collecting radio frequency. In the demo, we use the second way by utilizing USRP device and GNU Radio software to collect, analyze and replay the signal.
Signal Collection (2) GNU Radio Controller USRP Collected Signal
GNU Radio Modules
Collected Signal The signal that is collected by pressing the first turn on button. From the shape of the signal, we make an assumption that binary sequence from Microcontroller in controller is modulated by OOK (On-off keying) modulation. On-off keying (OOK) the simplest form of amplitude-shift keying modulation that represents digital Data as the presence or absence of a carrier wave.
Signal Analysis 0 1 1 0 1 0 0 0 1 0 0 0 0 0 0 0
Signal Analysis 0 1 1 0 1 0 0 0 1 0 0 0 0 0 0 0
Binary sequence Binary sequence for Turn ON 0 1 1 0 1 0 0 0 1 0 0 0 0 0 0 0 Binary sequence for Turn OFF 0 1 1 0 1 0 0 0 0 1 0 0 0 0 0 0
Final step 0110100010000000 GNU Radio USRP Wireless Outlet
Conclusion It is a very simple reverse engineering. We use USRP and GNR Radio to collect signal. Then we analysis the signal, and use a binary sequence to represent the signal. After that, we use USRP and GNU Radio to send similar signal. And the outlet is controlled by our signal. This method can be widely used in many scenarios. For example, some typical cases are garage gate remote opener, car gate controller, wireless toy controller, etc. USRP can be widely used in RF design area.