Nokia Corporation

Princeton University

Nokia Technologies Oy

Visa Koivunen

Jani Väre

Harri Juhani Pekonen

Jussi Vesma

Pekka Talmola

Tommi Auranen

Jukka A Henriksson

Anu Huttunen

Niko Kiukkonen

H Vincent Poor

Jarmo Rafael Lundén

Athina Petropulu

Yuanning Yu

Jukka Henriksson

In a digital broadband broadcast transmitter, digital data is time interleaved for transmission, and the time interleaved digital data is transmitted in a digital broadband broadcast transmission towards a plurality of receivers. A cellular transmitter is operated in an apparatus. In the same apparatus, the digital broadband broadcast transmission transmitted by the digital broadband broadcast transmitter is received, and the received digital broadband broadcast transmission is time deinterleaved.

Interoperability of digital broadcasting and cellular communication systems

A user equipment senses a plurality of wireless signals it receives; estimates cyclic correlation of the received signals using a multi-variate sign function; determines from the estimated cyclic correlation which ones of the signals are detected based on cyclostationarity present at known cyclic frequencies; and a frequency resource is selected for opportunistic communications based on the frequencies over which were received the signals that were determined to be detected. In specific embodiments, the multi-variate sign function is bivariate; the detected signals are primary user signals and the selected frequency resource avoids frequencies on which they were received; and/or the detected signals are secondary user signals and the selected frequency resource can either avoid those frequencies on which they were received or use those frequencies for the UE's own opportunistic communications.

Correlation-based detection in a cognitive radio system

In a first time interval TI a first frequency band FB is pseudorandomly selected from a designated spectrum, and a first analysis result is determined by sensing the first FB during the first TI and then transmitted. In a second TI a second FB is pseudorandomly selected from the designated spectrum, and a second analysis result is determined by sensing the second FB during the second TI and then transmitted. Where multiple devices do this the entire spectrum is sensed, each band by a subset of devices that changes at each TI, and so any unused or underutilized spectrum is searched by the collaborative spectrum sensing, which avoids propagation problems such as fading. Also, a central node can assure various collaborating users report different FBs in different TIs such that the subset of reporting users changes for at least one of the bands in each subsequent reporting TI. Sensing and communication can be performed in different portions of the same network defined transmission time interval.

Method and apparatus to select collaborating users in spectrum sensing

A system and method for blind estimation of carrier frequency offsets (CFOs) and separation of user signals in wireless communications systems are provided. Blind estimation of CFOs (i.e., without knowledge of the conditions of the transmitter or the transmission medium/channel) is carried out in order to improve reception quality by a wireless communications device. A received RF signal is over-sampled by a pre-defined over-sampling factor, and polyphase components are extracted from the over-sampled signal. The polyphase components are used to construct a virtual receiver output matrix, e.g., a model of the received signal and its associated output matrix. System response conditions are blindly estimated by applying a blind system estimation algorithm to the virtual receiver output matrix. A plurality of CFO estimates are obtained from the estimated system response conditions, and can be used by an equalizer to adjust receiver parameters in accordance with the CFO estimates so as to maximize reception quality and to extract multiple user signals from the received signal.

System and method for blind estimation of multiple carrier frequency offsets and separation of user signals in wireless communications systems

Aspects of the invention are directed to service and channel discovery in a digital broadcast network. A pilot synchronization symbol, which has known characteristics, is included as a first symbol of digital broadcast frames. The pilot symbol, which can be decoded without having to resort to trial and error methods, contains parameters for the rest of the signal. So, the rest of the signal can be decoded without trial and error methods after the pilot symbol (and any additional synchronization symbols) is decoded. Channels containing digital video broadcast services can be efficiently detected using the known part of the signal. If the fixed known part is not found from the examined signal, then the signal will be considered a non-digital-video-broadcast signal or an empty channel, and the receiver can promptly proceed to a next channel/frequency. In this way, detecting non-digital-video-broadcast and empty channels becomes relatively fast.

Digital broadcast service discovery correlation

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Espoo, Finland

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