Abstract: A method and system for detection of available a white space channel in an area of licensed transmitters includes a detector which utilizes the autocorrelation analysis of a channel in an frequency modulated (FM) band. Calculation of the autocorrelation excludes an initial set of correlation delay values such that large values of autocorrelation are removed. The remaining autocorrelation based on higher correlation delay values exposes the sinusoidal nature of an FM transmitter operating in the selected channel. White space becomes available to a user if no transmitter is detected using the autocorrelation detection method.

Abstract: Methods and apparatus for access, enablement and control of devices in TV white space are provided. Methods and apparatus for channel scanning by a device are provided that shorten channel scanning time by using a 5 MHz Measurement Pilot frame at a predetermined location within an enabling device's channel, regardless of the operating bandwidth of the enabling device. Also provided are methods and apparatus for multi-band dynamic station enablement that locate information regarding an enabling device's supported regulatory classes and channel numbers within one accessible frame of information and also provide request and response messages to arrange for enablement of a requesting device on a network. Further, methods and apparatus are provided for identifying an interfering device on a network by providing increased information from within a DSE Registered Location element.

Abstract: A method and apparatus for using 802.11 Wireless LANs in TV white space are provided that additionally allows coexistence with non-802.11 devices in the same spectrum space. The method and apparatus extend concepts used in traditional 802.11 applications in the MAC and PHY layers so that WLANs can function over TV white space channels. The method and apparatus also facilitates coexistence of non 802.11 devices and existence with other 802.11 applications by extending the Enhanced Distributed Channel Access mechanism used to provide quality of service. An OFDM system with fixed subcarrier spacing is suggested to accommodate spectrum characteristics (variable center frequency and channel bandwidth) of the TVWS.

Abstract: The invention relates to a wireless home gateway apparatus and methods of wirelessly delivering audio and/or video programs between a home gateway and a client device and to interference mitigation techniques on such system. Specifically, the invention relates to transmitting an audio video program on a first channel, receiving a control signal from a remote control indicating interference on said first channel, changing the transmission channel to a second channel, and transmitting data indicating said second channel to said remote control.

Abstract: A method and apparatus for spectrum sensing for general wireless microphone signals are provided. The spectrum sensing algorithm developed makes use of the property that the autocorrelation function of a wireless microphone signal is a sinusoidal function provided that the frequency deviation is much smaller than the carrier frequency and the correlation delay is small. Based on this property, a simple spectrum sensing algorithm for the wireless microphone signal is designed by computing the auto-correlation function of the received signal and matched filtering of the sinusoidal function. The tones detected are further verified to see if they are located at one of the possible wireless microphone frequencies.

Abstract: A communication device, such as a smart phone, includes logic to determine a noise power estimate. In an example, a frequency domain calculation may be used to determine noise components within the noise power estimate. Further, a product of a channel estimate and equalizer effect may be used in the determination of the levels noise components, such as, inter-symbol interference power and neighbor cell interference power.

Abstract: A frame header of Forward Error Correction (FEC) is provided, suitable for using in the DVB-C2 Standard. In the DVB-C2 Standard, Adaptive Coding and Modulation (ACM) or Variable Coding and Modulation (VCM) is applied to each FEC block to provide as much flexibility as possible. As a result, a frame header is attached in front of each FEC frame to inform the coding rate, modulation type and physical layer pipe identifier. Besides the signaling of physical layer related information, the FEC frame header has to provide a structure so that it can be easily and reliably detected in the receiver. Motivated by the need in DVB-C2 Standard, an efficient and reliable FEC header suitable for DVB-C2 Standard is provided in at least one implementation in this disclosure that combines use of two different modulation types for the header information. In addition, the detection Method of the FEC header is described.

Abstract: Code detection to assist a symbol-level equalizer in a receiver is described. In an embodiment, code detection uses adaptive Infinite Impulse Response (IIR) filtering to determine spreading code usage information and active code channels in a received signal. The spreading code usage information indicates if a spreading code associated with a code channel is among spreading codes used in the received signal. In another embodiment, the spreading code usage information is determined based on a forgetting factor associated with the filtering of a symbol power associated with the code channel.

Abstract: A frame header of Forward Error Correction (FEC) is provided, suitable for using in the DVB-C2 Standard. In the DVB-C2 Standard, Adaptive Coding and Modulation (ACM) or Variable Coding and Modulation (VCM) is applied to each FEC block to provide as much flexibility as possible. As a result, a frame header is attached in front of each FEC frame to inform the coding rate, modulation type and physical layer pipe identifier. Besides the signaling of physical layer related information, the FEC frame header has to provide a structure so that it can be easily and reliably detected in the receiver. Motivated by the need in DVB-C2 Standard, an efficient and reliable FEC header suitable for DVB-C2 Standard is provided in at least one implementation in this disclosure that combines use of two different modulation types for the header information. In addition, the detection Method of the FEC header is described.

Abstract: A communication device, such as a smart phone, includes logic to determine a noise power estimate. In an example, a frequency domain calculation may be used to determine noise components within the noise power estimate. Further, a product of a channel estimate and equalizer effect may be used in the determination of the levels noise components, such as, inter-symbol interference power and neighbor cell interference power.

Abstract: The invention relates to a wireless home gateway apparatus and methods of wirelessly delivering audio and/or video programs between a home gateway and a client and mitigating interference thereon. Specifically, the present invention relates to transmitting an audio/video program on two white space channels and alternately stopping transmission on one of said channels to search for external transmissions on the white space channel. The present invention permits the wireless home gateway to continuously transmit an audio/video program to a client while periodically searching for transmitters on each of the white space channels.

Abstract: Methods and apparatus of slot time synchronization for coexistence of 5 MHz, 10 MHz, and 20 MHz systems in TV white space are provided. The methods and apparatus extend concepts used in traditional 802.11 applications in the MAC layer so that networks that overlap in frequency and space can have access opportunities to TV white space channels. Several passive mechanisms are described which use bits of traditional 802.11 MAC Management Protocol Data Units to receive information related to the slot time of other overlapped networks. An active approach is described that uses measurements from a radio resource measurement service to adjust the slot time of stations in a network to that of the lowest bandwidth overlapped network in frequency and space.

Abstract: Methods and apparatuses for OFDM spectrum sensing are provided. The proposed spectrum sensing algorithms are based on Time-Domain Symbol Cross-Correlation (TDSC-MRC and TDSC-NP methods) and can be applied to all existing wireless OFDM systems. The statistical behaviors of the TDSC-based spectrum sensors are explicitly analyzed. In addition, the spectrum sensing method employing the Cyclic Prefix of the OFDM modulated signals (CP method) is described for comparison purposes. The DVB-T Standard is adopted as an application example to illustrate the proposed spectrum sensing algorithms. Simulation results show that the TDSC-MRC method outperforms the CP method for all values of CP ratio considered. The TDSC methods have the advantage that the detection performances are the same for different CP ratios, while the detection performance of the CP method degrades dramatically when the CP ratio becomes small.

Abstract: Methods and apparatus for FEC frame header detection are provided, suitable for use in a DVB-C2 receiver. A first method comprises demodulating with a quadrature phase shift keying (QPSK) demapper, followed by correlation and symmetry measures for detection of a robust FEC header. A second method comprises demodulating with a 16 quadrature amplitude modulation (QAM) demapper, followed by correlation and symmetry measures for detection of a high efficiency FEC leader. Another embodiment comprises using both the first and second methods to find the FEC header because the first symbol of the FEC frame header may be sent either in robust mode or in high efficiency mode. There is also provided a method and apparatus for generating an alternate decision statistic for determining detection of the FEC frame header.

Abstract: A method and apparatus are described including defining a neighbor set for each access point, selecting a first clock in a first access point, the selected clock having a highest accuracy as a grand master clock, advising neighboring access points to synchronize with the selected grand master clock and transmitting a message to schedule a quiet period based on the grand master clock. Also described are a method and apparatus including receiving a beacon message, inspecting clock descriptors in the beacon message, selecting a best master clock responsive to the inspection and transmitting a message to schedule a quiet period based on the selected best master clock.

Abstract: An apparatus comprises a downconverter for providing a signal that may be a received orthogonal frequency division multiplexed (OFDM) symbols from a selected channel, each OFDM symbol comprising N subcarriers at least some of which are pilot subcarriers; and a processor that (a) correlates the received OFDM symbols for providing at least one correlated value, (b) generates a metric value as a function of the at least one correlated value and (b) compares the metric value to a threshold value for detecting if an incumbent signal is present.

Abstract: Methods and apparatus for access, enablement and control of devices in TV white space are provided. Methods and apparatus for channel scanning by a device are provided that shorten channel scanning time by using a 5 MHz Measurement Pilot frame at a predetermined location within an enabling device's channel, regardless of the operating bandwidth of the enabling device. Also provided are methods and apparatus for multi-band dynamic station enablement that locate information regarding an enabling device's supported regulatory classes and channel numbers within one accessible frame of information and also provide request and response messages to arrange for enablement of a requesting device on a network. Further, methods and apparatus are provided for identifying an interfering device on a network by providing increased information from within a DSE Registered Location element.

Abstract: A Wireless Regional Area Network (WRAN) receiver comprises a transceiver for communicating with a wireless network over one of a number of channels, and a signal detector for use in forming a supported channel list comprising those ones of the number of channels upon which an Advanced Television Systems Committee (ATSC) DTV (digital television) broadcast signal was not detected. The signal detector performs spectrum sensing as a function of power spectral density (PSD) and cyclic spectrum.

Abstract: Methods and apparatus of slot time synchronization for coexistence of 5 MHz, 10 MHz, and 20 MHz systems in TV white space are provided. The methods and apparatus extend concepts used in traditional 802.11 applications in the MAC layer so that networks that overlap in frequency and space can have access opportunities to TV white space channels. Several passive mechanisms are described which use bits of traditional 802.11 MAC Management Protocol Data Units to receive information related to the slot time of other overlapped networks. An active approach is described that uses measurements from a radio resource measurement service to adjust the slot time of stations in a network to that of the lowest bandwidth overlapped network in frequency and space.

Abstract: Methods and apparatus for using 802.11 Wireless LANs in TV white space that allow networks with overlapping wireless regions to coexist. The methods and apparatus offer a solution to the mutated hidden node problem. Wireless devices communicate with a coexistence manager over a backhaul connection. Signals are sent by a low power station indicating a request to use a portion of spectrum. The coexistence manager communicates with a plurality of second stations that transmit at a higher power level. The plurality of second stations either send a signal to the first station indicating that it can transmit, or send signals so that the first station can determine which interference it is receiving, after which the coexistence manager tells the interfering station to transmit a signal to the first station indicating when it can transmit.