Ultra-Wideband (UWB) Wireless Technology

JasonYoo

Ultra-Wideband (UWB) Wireless Technology [Copy link]

Ultra-wideband (UWB) is a wireless radio frequency technology that enables home appliances, computer peripherals, and mobile devices to transmit data at high speeds over short distances while consuming very little power. The technology is ideal for wireless transmission of high-quality multimedia content. UWB technology uses a wideband wireless spectrum to transmit data over short distances (such as within a home or small office), allowing it to transmit more data wirelessly in a given period of time than traditional wireless technologies. This feature, combined with low-power pulsed data delivery, speeds up data transmission while also being immune to interference from other existing wireless technologies such as Wi-Fi, WiMAX, and cellular wide-area communications.

　　Impulse radio (IR) is one of the most promising UWB technologies. IR signals consist of very narrow pulses that occur pseudo-randomly in time. Pseudo-randomness is achieved by time-hopping codes, which randomize the transmitted signal to facilitate user separation and spectrum shaping to prevent eavesdropping. The signal can be modulated using pulse amplitude modulation (PAM) or pulse position modulation (PPM). To ensure low-cost UWB devices, all pulses have the same waveform.

　　Compared with existing wireless communication technologies, the communication carrier used by UWB wireless communication technology is a continuous radio wave. Figuratively speaking, this radio wave is like a person holding a hose to water the lawn, and the water in the hose forms a continuous water flow fluctuation as the hand moves up and down. Almost all wireless communications, including mobile phones and wireless LAN communications, are like this: the signal is loaded on a continuous radio wave using a certain modulation method. In comparison, UWB wireless communication technology is like a person using a rotating sprinkler to water the lawn, which can spray more and faster short water pulses. UWB products can send a large number of very short and very fast energy pulses when working. These pulses are precisely timed, each only a few nanoseconds long, and the pulses can cover a very wide area.

　　Ultra-wideband technology brings an advantage that the circuit is simpler, especially at the receiving end, because there is no need to generate carriers locally, nor is it necessary to provide multi-stage hybrid circuits, shaping filters, etc. However, the advantages brought by using carrier spread spectrum outweigh ultra-wideband technology. Ultra-wideband itself is a type of baseband signal (although its spectrum range reaches several GHz). In this case, the propagation characteristics of the near-DC and mid-range parts of the spectrum have different characteristics, which limits this technology to short-distance communications. For long-distance communications, especially relaying, spread spectrum technology is more suitable.