A method and system that provides for execution of a first calibration sequence, such as upon initialization of a system, to establish an operation value, which utilizes an algorithm intended to be exhaustive, and executing a second calibration sequence from time to time, to measure drift in the parameter, and to update the operation value in response to the measured drift. The second calibration sequence utilizes less resources of the communication channel than does the first calibration sequence. In one embodiment, the first calibration sequence for measurement and convergence on the operation value utilizes long calibration patterns, such as codes that are greater than 30 bytes, or pseudorandom bit sequences having lengths of 2.sup.N−1 bits, where N is equal to or greater than 7, while the second calibration sequence utilizes short calibration patterns, such as fixed codes less than 16 bytes, and for example as short as 2 bytes long.

A method and system that provides for execution of a first calibration sequence, such as upon initialization of a system, to establish an operation value, which utilizes an algorithm intended to be exhaustive, and executing a second calibration sequence from time to time, to measure drift in the parameter, and to update the operation value in response to the measured drift. The second calibration sequence utilizes less resources of the communication channel than does the first calibration sequence. In one embodiment, the first calibration sequence for measurement and convergence on the operation value utilizes long calibration patterns, such as codes that are greater than 30 bytes, or pseudorandom bit sequences having lengths of 2.sup.N−1 bits, where N is equal to or greater than 7, while the second calibration sequence utilizes short calibration patterns, such as fixed codes less than 16 bytes, and for example as short as 2 bytes long.

A method for automatically detecting a packet mode in a wireless communication system supporting a multiple transmission mode includes: acquiring at least one of data rate information, packet length information and channel bandwidth information from a transmitted frame; and determining the packet mode on the basis of the phase rotation check result of a symbol transmitted after a signal field signal and at least one of the data rate information, the packet length information and the channel bandwidth information acquired from the transmitted frame.

A decentralized communication device is provided that facilitates optimal positioning and orientation of one or more antennas for wireless communication with external devices. The decentralized communication device includes one or more master components and one or more slave components. The master and the slave components are physically separate and communicate wirelessly. In some embodiments the slave acts as a carrier frequency translator between the master and an external wireless device, where it communicates with the external device using a first frequency and communicates with the master using a second frequency which is different from the first frequency. In another embodiment the slave has most or all the physical layer to do the digital coding, digital modulation, data framing, data formatting and data packetization for communicating with an external device, in which case digital coding and digital modulation is distributed between the master and the slave.

Mixed mode constellation mapping to map a data block to a block of sub-carriers based on a configurable set of one or more constellation mapping schemes, and corresponding mixed mode least likelihood ratio (LLR) de-mapping based on the configurable set of one or more modulation schemes. The set may be configurable to include multiple modulation schemes to provide to a SEvSNR measure that is a non-weighted or weighted average of SEvSNR measures of the multiple modulation schemes. Mixed mode constellation mapping may be useful be configurable to control spectral efficiency versus SNR (SEvSNR) over a range of SNR with relatively fine SNR granularity, and may be configurable to control SEvSNR over a range of SNR at a fixed FEC code rate, which may include a highest available or highest permitted code rate.

A method for receiving a downlink signal by a user equipment (UE) in a wireless communication system supporting an unlicensed band, includes monitoring a set of Physical Downlink Control Channel (PDCCH) candidates for receiving a PDCCH in subframe # n−1 of the unlicensed band, wherein n is an integer larger than 1; receiving a first PDCCH in subframe # n of the unlicensed band, wherein the first PDCCH includes information for indicating that a number of occupied symbols in the subframe # n is less than 14; and receiving, from a base station (BS), a second PDCCH including uplink scheduling information in the subframe # n based on that the UE does not receive the PDCCH in the subframe # n−1 and receives the first PDCCH.

Apparatus and methods for identifying a wireless signal-emitting device are disclosed. The apparatus is configured to sense and measure wireless communication signals from signal-emitting devices in a spectrum. The apparatus is operable to automatically detect a signal of interest from the wireless signal-emitting device and create a signal profile of the signal of interest; compare the signal profile with stored device signal profiles for identification of the wireless signal-emitting device; and calculate signal degradation data for the signal of interest based on information associated with the signal of interest in a static database including noise figure parameters of a wireless signal-emitting device outputting the signal of interest. The signal profile of the signal of interest, profile comparison result, and signal degradation data are stored in the apparatus.

A base station may determine a root for a sequence to be included in a signal to a UE. The base station may generate a generalized Chu sequence based on the root and scramble the generalized Chu sequence using a pseudorandom sequence that is common to a plurality of base stations. The base station may transmit the scrambled generalized Chu sequence to indicate the beginning of a downlink transmission. The UE may receive this scrambled generalized Chu sequence and determine if a beginning of a downlink transmission from a serving base station based on the received generalized Chu sequence and an expected generalized Chu sequence.

Systems, methods, and apparatus are provided for automated identification of baseline data and changes in state in a wireless communications spectrum, by identifying sources of signal emission in the spectrum by automatically detecting signals, analyzing signals, comparing signal data to historical and reference data, creating corresponding signal profiles, and determining information about the baseline data and changes in state based upon the measured and analyzed data in near real time, which is stored on each apparatus or device and/or on a remote server computer that aggregates data from each apparatus or device.

Systems, methods, and apparatus are provided for automated identification of baseline data and changes in state in a wireless communications spectrum, by identifying sources of signal emission in the spectrum by automatically detecting signals, analyzing signals, comparing signal data to historical and reference data, creating corresponding signal profiles, and determining information about the baseline data and changes in state based upon the measured and analyzed data in near real time, which is stored on each apparatus or device and/or on a remote server computer that aggregates data from each apparatus or device.