摘要:
A first detector receives a received signal and extracts the data signals from the received signal. A hard decision converter converts soft symbols outputted by the first detector into hard symbols. An interference canceller extracts the voice signals from the received signal. A second detector is connected to the output of the interference canceller, and extracts the individual voice signals. The second detector is a different detector type than the first detector.
摘要:
A “smart antenna” method and system for use in cellular networks where the wireless transmit receive unit and/or the base station utilize multi-user detection (MUD). The interference to and from other users is taken into consideration to maximize the desired signal while eliminating or reducing interfering signals, thereby increasing overall system capacity.
摘要:
A system and method for estimating the frequency offset experienced between carrier and local oscillator frequencies in communication systems using quadrature modulation. The invention exploits the geometry of the quadrature modulation constellation and estimates actual offset within a predefined carrier offset value without requiring data estimation.
摘要:
A “smart antenna” method and system for use in cellular networks where the wireless transmit receive unit and/or the base station utilize multi-user detection (MUD). The interference to and from other users is taken into consideration to maximize the desired signal while eliminating or reducing interfering signals, thereby increasing overall system capacity.
摘要:
A system for estimating carrier offset includes includes a transmitter configured to transmit a quadrature modulated signal, and a receiver. The receiver includes an input configured to receive the quadrature modulated signal, a local oscillator configured to generate cosine and sine waves at a carrier frequency of the quadrature modulated signal, at least one cosine mixer configured to generate a carrier frequency demodulated output, at least one sine mixer configured to generate a carrier frequency demodulated output, a plurality of lowpass filters configured to filter the demodulated output of the cosine and sine mixers to produce filtered cosine and sine signal components, and a carrier offset detection processor to estimate a carrier offset between the carrier frequency and a local oscillator frequency based on the filtered output of the lowpass filters.
摘要:
The present invention relates to secret key generation and authentication methods that are based on joint randomness not shared by others (JRNSO), in which unique channel response between two communication terminals generates a secret key. Multiple network access points use a unique physical location of a receiving station to increase user data security. High data rate communication data is encrypted by generating a random key and a pseudo-random bit stream. A configurable interleaving is achieved by introduction of JRNSO bits to an encoder used for error-correction codes. Databases of user data are also protected by JRNSO-based key mechanisms. Additional random qualities are induced on the joint channel using MIMO eigen-beamforming, antenna array deflection, polarization selection, pattern deformation, and path selection by beamforming or time correlation. Gesturing induces randomness according to uniquely random patterns of a human user's arm movements inflected to the user device.
摘要:
Techniques for sending an aggregated beacon in a cognitive wireless network are disclosed. A beacon device may segment beacon information and send beacon segments via a plurality of channels simultaneously. A certain information elements of the beacon information may be included in each beacon segment. Each beacon segment may include channel information for other beacon segments that are transmitted simultaneously. Alternatively, a discovery beacon may be transmitted in addition to a regular beacon. The discovery beacon may include information indicating an operating channel on which the regular beacon is transmitted. The discovery beacon may be transmitted using a predetermined channel bandwidth, with a smaller beacon interval than the regular beacon, or in a frequency hopping fashion. The discovery beacon may be sent on a channel selected based on a regulatory class and corresponding channel information. The discovery beacon may be transmitted on a side channel.
摘要:
A method for managing channel selection in a dynamic spectrum management network includes receiving a spectrum allocation request; based on the source of the spectrum allocation request, checking for available channels; based on the source of the spectrum allocation request, collecting sensing and usage data for the available channels; providing the channel usage data to an entity that transmitted the spectrum allocation request.
摘要:
Systems and methods for dynamic white space management are described. First, local handling of channel queries, in which a channel query by a white space device (WSD) is handled by a local dynamic spectrum management (DSM) server, if the DSM server has all the information necessary for providing a response to the channel query. Second, a search extension, in which a WSDB passes part of a search for available channels to a local DSM server. Third, assisting of an available channel calculation, in which a DSM server provides spectrum sensing information to WSDBs to improve the available channel calculation within the WSDBs. And fourth, dynamic bandwidth management to meet the coexistence requirements. In addition, the content of the messages and procedures that enable the above value-adding functions and interactions with the WSDB systems are described.
摘要:
A method for transmitting an encrypted signal to a wireless transmit/receive unit (WTRU) such that decryption of the encrypted signal depends on a trust zone associated with the WTRU is disclosed. The encryption may be performed using hierarchical modulation, scrambling, authentication, location validation, or a combination thereof. The size of a trust zone may also be adjusted.