UWB UWB (UltraWideband) began in the 20th century the rise of the pulse of 60 years Communicate Technology, using a very wide spectrum of ultrashort pulses for communication, also known as base-band communication, no carrier communication. Due to its low power, high bandwidth, high transmission rate, low complexity, and strong resistance to multipath, low transmission signal power spectral density, high security advantages of UWB technology are expected in the next few years and are closely related to people's lives figure Home Appliances And consumer networking equipment to get the promotion, the cable television networks and home networks will be widely applied. 1, the basic principle of ultra-wideband technology 2002 2 , Federal Communications Commission (FCC) revised the 15 criteria, defined as the relative bandwidth of UWB signal (signal bandwidth and center frequency ratio) is greater than 0.2, or at any time in the transmission bandwidth is not small absolute on the 500MHz signal, which signal bandwidth is defined as: the maximum transmit power 10dB lower than the cutoff frequency of the bandwidth between. FCC also provides, UWB frequency range is the use of 3.1 ~ 10.6GHz, and the transmission power must be less 1mW. Compared with traditional communication systems, UWB systems has its unique of. Speaking from the time domain, the general communication system is carried out by sending radio frequency carrier signal modulation, while UWB is used, the placement of time-domain pulse (several nanoseconds) to achieve a direct modulation, the transmission of ultra-wideband modulation information to the process of release in a very wide frequency hand, and to the process to determine the duration of the occupied bandwidth of the frequency range. Speaking from the frequency domain, UWB is different from traditional narrowband and broadband, its wider frequency band. Narrowband refers to the relative bandwidth of less than 1% relative bandwidth of 1% to 25% and known as broadband, and the relative bandwidth of more than 25%, and the center frequency is greater than 500MHz, known as ultra-wideband. 2, Ultra-wideband technology in the home network application 1. Home Network Home network system consists of cable systems and wireless systems integration form. Among them, the cable system uses the international digital interface standard IEEE1394b, in IEEE1394b based on the home network wireless system into a spectrum efficient UWB impulse radio technology to provide flexibility and mobility of broadband wireless access. DS sequence UWB home network to wireless mobile high-speed high-performance seamless extension to the wired backbone 1394. 2. Subnet direct sequence ultra wideband communications technology Single-band system, DS-UWB system is the ideal home network program. DS- CD MA proposed dual band (3.1 ~ 5.15GHz plus 5.825 ~ 10.6GHz) method, which more than 1GHz, each band of data with very short pulses, the method also known as impulse radio. DS-UWB wireless communication system structure shown in Figure 1. 1394 bridge and wireless home network architecture to support integrated IEEE1394 fixed connections and DS-UWB wireless connection. Wireless UWB bus system topology is to present the star, HUB location is not fixed, the management of all hang in the wireless bus sub-stations, responsible for maintaining the frame structure, distribution cycle timing information. To monitor the registration of the bus stations of the state, in the sub-stations and sub-stations between Broadcasting Communication quality information, such as when the display mode of synchronization and time slot sub-station arrangement, multiple access control process to ensure the output power under a certain level. Data stream transmission is self-organizing networks such as communication patterns on, when a direct link between station pairs were separated, the child station and repeater HUB can also take a number of data. Direct sequence ultra-wideband physical layer system binary phase shift keying modulation technique, in order to avoid the impact of multipath fading, RAKE receiver using the received signal. The multiple access technology uses DS-CDMA technology. As the special nature of UWB signal generation, We are high quality suppliers, our products such as Plastic Masterbatches Manufacturer , Plastic Granules Manufacturer for oversee buyer. To know more, please visits Black Masterbatch.
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