Frequently Asked Questions

General

Using USRPs in Netbed


General

What is software-defined radio (SDR)?

Software-defined radio (SDR) is a system in which changeable software is used to process digital signals sent and/or received by accompanying radio frequency hardware. This is in contrast to traditional radios, in which the signal processing logic is mainly hard-coded into custom hardware with only limited control over how the signal is handled.

What is GNU Radio?

GNU Radio is a free, extensible software kit for experimenting with software defined radio (SDR) that runs on a general-purpose computer, such as a PC or a Mac. This software suite is normally coupled with hardware (such as the USRP) that captures radio frequency (RF) signals and converts them from analog to digital. The GNU Radio software operates on this digital representation of the radio signal.

What is the Universal Software Radio Peripheral (USRP)?

The Universal Software Radio Peripheral, or USRP for short, is a hardware platform designed to work with the GNU Radio software kit. It is comprised of an extensible motherboard that can accommodate up to four peripheral daughtercards. digital to analog (D/A) and analog to digital (A/D) converters on the motherboard change the signal to and from digital as it passes between the the motherboard and daughtercards. A programmable FPGA on the motherboard can perform mathematical transforms on the digital signals quickly. Data is shuttled to and from the motherboard and general purpose computer through a USB 2.0 connection.

Several USRP daughtercards are already available, with many more planned. These include a UHF receiver (50MHz–800MHz), basic transmit and receive boards for use with external equipment, and ISM band transmitters and receivers (e.g. 2.4GHz band).

Other technical information can be found on the Ettus Research Web page at http://www.ettus.com/.

Where can I buy USRPs?

The USRP is now available for purchase from Ettus Research.

If I can't afford to buy a bunch of USRPs, can I "borrow" some for my research and/or my class?

To be written.


Using USRPs in Netbed

How many USRPs are in Netbed? Where are they located? What are their characteristics?

To be written.

How do I get access to the USRPs in Netbed?

To be written.

Is the GNU Radio software already installed on Netbed?

To be written.

How do I create an experiment that uses Netbed's USRPs?

To be written.

How that I've created an experiment, how should I configure and use the USRPs?

To be written.

Can I choose USRP-enabled nodes based on their observed wireless properties with respect to each other, e.g., signal strength?

To be written.

How do I make sure that I get the same physical USRP nodes every time I run my experiment?

To be written.

Are there any sample experiments that I can play with?

To be written.