摘要:
A PHY entity for a UWB system utilizes the unlicensed 3.1-10.6 GHZ UWB band, as regulated in the United States by the Code of Federal Regulation, Title 47, Section 15. The UWB system provides a wireless pico area network (PAN) with data payload communication capabilities of 55, 80, 110, 160, 200, 320 and 480 Mb/s. The UWB system employs orthogonal frequency division multiplexing (OFDM) and uses a total of 122 sub-carriers that are modulated using quadrature phase shift keying (QPSK). Forward error correction coding (convolutional coding) is used with a coding rate of 11/32, 1/2, 5/8 and 3/4.
摘要:
System and method for simplifying preamble detection and reducing power consumption in receivers. A preferred embodiment comprises a preamble made up of two sequences, a first sequence that is specified in the time domain and a second sequence that is specified in the frequency domain. The first sequence which comprises multiple copies of a time domain code sequence can allow easy detection of the preamble while the second sequence comprises multiple copies of a frequency domain code sequence and allows easy determination of the frequency response of the communications channel. A hierarchical sequence can be used to allow multi-stage correlation. This can result in a less complex correlator, hence lower power consumption. Piconets can use different code sequences to allow rapid determination of the source of a transmission without requiring the receiver to decode the entire transmission.
摘要:
A method. The method includes producing a first signal match indication based on at least one match indication indicative of a match between at least one signal received in at least one band and a reference signal. The method also includes producing a first signal multipath combined signal based upon the first signal match indication, and detecting a first peak in the first multipath combined signal.
摘要:
A system and method implement very high data rate baseband DACs suitable for wireless applications related to new standards (e.g. Ultra-Wide Band) using CMOS processes allowing an integrated solution with the deep-submicron CMOS digital baseband. A single CMOS block working at full speed is discarded in favor of several blocks, each working at a fraction of the original data rate.
摘要:
A technique for generating carrier frequencies with fast hopping capability associated with multiband systems for ultra wideband applications. The technique employs a single VCO 20 that is locked in a PLL 30. The output of this VCO 20 is divided in the frequency domain. The divided frequencies thus obtained are combined in a single-sideband manner to obtain various other frequencies. The single-sideband combination requires open loop operations such as multiplication and addition or subtraction to implement, and hence is very fast. The VCO center frequency is not disturbed in the process. Since the required frequencies are generated in an open-loop fashion, instead of inside a PLL, the speed is increased by orders of magnitude.
摘要:
System and method for providing multiple access in a multi-band, orthogonal frequency division multiplexed (multi-band-OFDM) communications system. A preferred embodiment comprises determining a transmission bandwidth to support a performance requirement and configuring transmission bands in the multi-band-OFDM communications system based upon the transmission bandwidth, wherein the transmission bands may be made up of smaller transmission bands bonded together. Further comprising initializing communications with the configured transmission bands. The use of bonded transmission bands can provide increased data rates and/or increased range performance.
摘要:
A device (104, 106, 108) is provided for wireless communication. The device (104, 106, 108) includes a transmitter (200) operable to transmit an orthogonal frequency division multiplex symbol. The orthogonal frequency division multiplex symbol has a first set of copied tones adjacent a first end of the orthogonal frequency division multiplex symbol, a second set of copied tones adjacent a second end of the orthogonal frequency division multiplex symbol, and a plurality of data tones provided between the first and second sets of copied tones. The first and second sets of copied tones include copies of at least some of the plurality of data tones.
摘要:
The present invention provides a versatile system for selectively spreading carrier data across multiple carrier paths within an Orthogonal Frequency Division Multiplexing (OFDM) system (200), particularly an ultra-wideband (UWB) system. The present invention provides a data input (202), which passes data to a randomizer (204). The data then passes to a convolutional code function (206), the output of which is punctured by puncturing function (208). An interleaver function (210) receives the punctured code data, and cooperatively operates with a mapper element (218) to prepare the coded data for pre-transmission conversion by an IFFT (220). The mapper element (218) comprises a dual carrier modulation function (216), which associates and transforms two punctured code data elements into a format for transmission on two separate signal tones.
摘要:
The present invention provides a versatile system for optimizing data fragmentation in a digital communications—particularly OFDM communications—system. A digital transmission system (100) is provided, having a PHY-level constraint. An array (104, 112) of data transmission parameters (106-110, 114-116), relating to the digital transmission system, is provided. A fragmentation construct (102) is provided, and adapted to determine a number of symbols required to transmit a given data transmission payload. The fragmentation construct calculates (118), based on the number symbols required, and on certain parameter information from the array, a number of bytes of data that must be transmitted in the given data transmission payload in order to minimize pad bits added to the data transmission payload.
摘要:
A system and method for channelization and data multiplexing in ultra-wideband (UWB) wireless communication system is described. The spectrum allocated for UWB in a multi-band OFDM (orthogonal frequency division multiplex) system is subdivided into various bands. A set of time frequency codes (TFC's) is defined, wherein each code specifies one of a plurality of unique band versus time sequences for a particular band group, for sequential data symbols of a given piconet. The separation of data words from multiple devices or multiple simultaneously operating piconets (SOP's) is provided by a combination of FDMA and TFC's. The combination of FDMA and TFC's provides a simplified interface between the MAC and PHY.