Abstract: A communication system including a transmitter and a receiver is disclosed. The transmitter transmits frames, at least two consecutive frames containing different training sequences. The receiver receives data communicated from the transmitter over a channel. The receiver combines and jointly processes the at least two consecutive frames transmitted by the transmitter to estimate a channel state of the channel.

Abstract: Disclosed is a user terminal for wireless communication with a remote access point. The user terminal may include a mapping module adapted to map one or more input data bits to an uplink symbol, a delay module adapted to apply a delay to the uplink symbol, a transmit module adapted to modulate the delayed symbol into a frequency channel, and an antenna being adapted to transmit the modulated symbol to the access point. The delay can be chosen such that the transmitted symbol arrives at the access point simultaneously with a further symbol modulated into the frequency channel and transmitted by a further user terminal.

Abstract: Disclosed is a user terminal for wireless communication with a remote access point. The user terminal may include a mapping module adapted to map one or more input data bits to an uplink symbol, a delay module adapted to apply a delay to the uplink symbol, a transmit module adapted to modulate the delayed symbol into a frequency channel, and an antenna being adapted to transmit the modulated symbol to the access point. The delay can be chosen such that the transmitted symbol arrives at the access point simultaneously with a further symbol modulated into the frequency channel and transmitted by a further user terminal.

Abstract: Disclosed is a user terminal for wireless communication with a remote access point, the user terminal comprising: a mapping module adapted to map one or more input data bits to an uplink symbol; a delay module adapted to apply a delay to the uplink symbol; a transmit module adapted to modulate the delayed symbol into a frequency channel; and a directional antenna oriented along a dominant path to the access point, the antenna being adapted to transmit the modulated symbol to the access point, wherein the delay is chosen such that the transmitted symbol arrives at the access point simultaneously with a further symbol modulated into the frequency channel and transmitted by a further user terminal.

Abstract: Disclosed is a user terminal for wireless communication with a remote access point, the user terminal comprising: a mapping module adapted to map one or more input data bits to an uplink symbol; a delay module adapted to apply a delay to the uplink symbol; a transmit module adapted to modulate the delayed symbol into a frequency channel; and a directional antenna oriented along a dominant path to the access point, the antenna being adapted to transmit the modulated symbol to the access point, wherein the delay is chosen such that the transmitted symbol arrives at the access point simultaneously with a further symbol modulated into the frequency channel and transmitted by a further user terminal.

Abstract: An OFDM wireless communication system with an access point and a plurality of remote user terminals estimates an uplink channel. The access point receives training symbols transmitted by the user terminals. Each training symbol includes pilot symbols associated with phase offset estimation OFDM sub-carriers. The phase offset estimation sub-carriers include subsets of sub-carriers associated with each respective user terminals. Each subset is used exclusively by the associated user terminal during channel estimation. The channel estimation sub-carriers are used by all user terminals. For each terminal the access point estimates symbol-specific phase offsets specific to the user terminal using the received pilot symbols associated with the user specific subset of the phase offset estimation sub-carriers. The access point also estimates the uplink channel using the user-terminal-symbol-specific phase offset estimates and the received symbols.

Abstract: A user terminal for wireless communication with a remote access point can include a mapping module, a delay module, a transmit module, and a directional antenna. The mapping module can be used to map one or more input data bits to an uplink symbol. The delay module can be used to apply a delay to the uplink symbol. The transmit module can be used to modulate the delayed symbol into a frequency channel. The directional antenna can be oriented along a dominant path to the access point, and the antenna is used to transmit the modulated symbol to the access point. The delay is chosen such that the transmitted symbol arrives at the access point simultaneously with a another symbol that is modulated into the frequency channel and transmitted by another user terminal.

Abstract: A circuit for transmission and reception of multi-channel communications is disclosed. The transmitter path includes a digital modulation circuit receiving multiple channel binary data, and for each channel generating a digital representation of the data. A digital-to-analogue (D/A) conversion circuit (140-146) is provided for each data channel. Each D/A conversion circuit receives and converts respective channel digital representations to produce a resultant band limited analogue signal (148-154). The band limitation arises due to a characteristic of said channel digital representations. A bandpass filter (156-162) receives and filters each analogue channel signal. The band width to the start of the stop band of each bandpass filter is wider than a respective band limited analogue channel signal and wider than the Nyquist bandwidth arising from the sampling rate of said D/A conversion circuit. In this way, signal power in unwanted Nyquist zones is effectively removed.

Abstract: Disclosed is an OFDM wireless communication system comprising an access point, and a plurality of remote user terminals. The access point receives one or more training symbols transmitted by the user terminals, each training symbol comprising pilot symbols associated with phase offset estimation OFDM sub-carriers of said training symbol, the phase offset estimation sub-carriers comprising subsets of sub-carriers associated with respective user terminals, wherein each subset is used exclusively by the associated user terminal during channel estimation, and further symbols associated with channel estimation OFDM sub-carriers of said training symbol, wherein the channel estimation sub-carriers are used by all user terminals.

Abstract: A circuit for transmission and reception of multi-channel communications is disclosed. The transmitter path includes a digital modulation circuit receiving multiple channel binary data, and for each channel generating a digital representation of the data. A digital-to-analogue (D/A) conversion circuit (140-146) is provided for each data channel. Each D/A conversion circuit receives and converts respective channel digital representations to produce a resultant band limited analogue signal (148-154). The band limitation arises due to a characteristic of said channel digital representations. A bandpass filter (156-162) receives and filters each analogue channel signal. The band width to the start of the stop band of each bandpass filter is wider than a respective band limited analogue channel signal and wider than the Nyquist bandwidth arising from the sampling rate of said D/A conversion circuit. In this way, signal power in unwanted Nyquist zones is effectively removed.