Introduction

Nutaq’s WD20 RF wideband digitizer is designed for applications involving spectrum sensing, spread spectrum techniques, or ultra-wideband (UWB). In this post, we take a quick look at these applications, see what fields they apply to, and learn how the WD20 is ideal for implementing them.

Ultra-wideband

Ultra-wideband (UWB) is a radio technology characterized by very short impulses. The shortness of the impulses makes their bandwidth very large. Unlike traditional waveforms, UWB waveforms use pulses rather than channel-specific frequency components. This approach uses what is called carrier free direct sequence ultra wideband technology. Communications of this type are very accurate and less noise-sensitive because of their small time-spread. Another type of UWB technology involves OFDM waveforms that are around 500 MHz wide. In both cases, the signal is very spread in spectrum and faces many regulatory issues.

The development of this technology started in the 1960’s but was relatively slow because of several factors, most notably being legislation by regulatory organizations such as the Federal Communications Commission (FCC). Because UWB signals are very spread in frequency, they are more difficult to fit in legislation than when blocks of frequencies are reserved for specific applications. In the U.S., the FCC has approved ultra wideband technology for indoor short-range communication, with some restrictions on the frequencies.

In the radar and sensing fields, applications include sensor data collection, precision locating,  and tracking. In communication fields, UWB is used for achieving a very high-bandwidth under short ranges. All of these can be used in both commercial and military applications.

Applications :

Commercial:

  • High-speed LAN/WAN ( >20 Mbps)
  • Avoidance radar
  • Altimeter (aviation)
  • Tags for intelligent transport systems
  • Intrusion detection
  • Geo-location

Military:

  • Radar
  • Covert communications
  • Intrusion detection
  • Precision geo-location
  • Data links

Spread spectrum techniques

Other type of technology using a wide bandwidth is spread spectrum. In this method, a signal with a defined bandwidth is spread in the frequency domain to take on a very large bandwidth. Some applications use this technique to establish secure communications that are resistant to natural interference, noise and jamming.

The WD20: Nutaq’s wideband digitizer for the PicoDigitizer250

Conclusion

Many technologies may require the use of a wide bandwidth receiver. With today’s research into spectrum sensing for cognitive radio applications, especially from an Internet Of Things (IoT) perspective, this kind of receiver is even more necessary. Nutaq’s WD20G RF wideband digitizer is tunable from 100 kHz to 20 GHz, making it suitable for all the technologies discussed in this blog post.

Sources :

http:/https://www.nutaq.com.wikipedia.org/wiki/Ultra-wideband
http://www.radio-electronics.com/info/wireless/uwb/ultra-wideband-technology.php
http:/https://www.nutaq.com.wikipedia.org/wiki/Spread_spectrum