Telefonaktiebolaget Lm Ericsson (publ)

Ericsson Gmbh

Ericsson Ge Mobile Communications Inc.

Martin Isberg

Peter Jakobsson

Torsten John Carlsson

Magnus Nilsson

Jan Celander

Magnus Sandgren

Kjell Berthold Gustafsson

Bjorn Martin Lindquist

Jacob Mannerstrangle

William O Camp, Jr

John G Freed

Heino Jean Wendelrup

Dandan Hao

Bo Lindell

Hans Hagberg

Per Ingelhag

Joakim Plahn

Peter Svensson

Sten Wallin

Björn Lindqvist

Martin Sallenhag

Lars Peter Kunkel

Örjan Renström

Agneta Ljungbro

Lars-Peter Kunkel

Frank Lombardi

In an example embodiment, a system comprises a chain of serially coupled nodes, including a central processing node (CPN) and one or more radio communications nodes (RCNs). The CPN couples to a first RCN in the chain via a dielectric waveguide (DWG) link and any further RCNs in the chain are successively connected in serial fashion from the first RCN via further (DWG) links. The CPN generates outbound radio carrier signals that are waveguide-propagated in a downstream direction of the chain, for over-the-air (OTA) by targeted ones of the RCNs, while radio carrier signals received via OTA reception by respective ones of the RCNs are waveguide propagated as inbound radio signals in an upstream direction of the chain, for processing by the CPN. Advantages from he contemplated system include greatly simplified implementation of the RCNs, with lower cost and power consumption. Further, strategic placement of failover CPNs and DWG links provide for continued operation in the face of CPN or DWG link failures.

Method and apparatus for radio communications

A distributed wireless system comprises controlling node and two or more antenna processing nodes communicatively coupled to the controlling node but spatially separated from each other and from the controlling node. The controlling node sends commands to and exchanges data with a first subset of the antenna processing nodes, using a first twisted-pair lane of a physical layer interface having four twisted-pair lanes, and sends commands to and exchanging data with a second subset of the antenna processing nodes, using a second twisted-pair lane. In some embodiments, the controlling node also uses a third twisted-pair lane for communicating with the first subset, while using the fourth twisted-pair lane for communicating with the second subset. Corresponding antenna processing nodes terminate one or two twisted-pair lanes in a direction towards the controlling node, while terminating one or two twisted-pair lanes towards one or more antenna processing nodes further from the controlling node.

Interface in series-connected radios

A first antenna processing node receives () one or more wireless transmissions from a wireless device and obtains first symbol values from the one or more wireless transmissions. The first antenna processing node receives () second symbol values from a second antenna processing node, the second symbol values corresponding to the one or more wireless transmissions as received at the second antenna processing node, and calculates () a first weight parameter based on at least a subset of the first symbol values and a corresponding subset of the second symbol values. The first antenna processing node calculates () third symbol values by computing a weighted sum of first symbol values and corresponding ones of the second symbol values, using the first weight parameter, and sends () the third symbol values to a third antenna processing node or to a controlling node. This combining of symbol values may approximate maximum ratio combining, MRC.

Coherent summing of signals from distributed radio access points

A wireless system comprises a controlling node and two or more antenna processing nodes coupled to the controlling node but separated from each other. The controlling node sends () a command to a first one of the two or more antenna processing nodes, instructing the first one of the two or more antenna processing nodes to transmit data to a wireless device. This may be preceded by selecting () the first one of the antenna processing nodes based on an estimated signal quality metric corresponding to the wireless device for each antenna processing node. In response to a determination by the controlling node that the wireless device has not successfully decoded the data, the controlling node sends () a command to a second one of the two or more antenna processing nodes, instructing the second one of the antenna processing nodes to transmit the data to the wireless device.

Hybrid automatic repeat request (ARQ) with spatial diversity

A wireless system comprises a controlling node and multiple antenna processing nodes coupled to the controlling node but separated from each other. The controlling node receives () first soft bit information from a first antenna processing node, the first soft bit information corresponding to reception of a wireless transmission. Responsive to determining that it cannot decode transmitted bits using the first soft bit information, the controlling node requests () and receives () second soft bit information from a second antenna processing node, the second soft bit information also corresponding to the first wireless transmission from the wireless device and having been buffered by the second antenna processing node. The controlling node decodes () bits from the first wireless transmission using both the first and second soft bit information. The controlling node may then signal the antenna processing nodes that they can discard buffered information for the wireless transmission.

Chase combining in a distributed wireless system

A method is disclosed for controlling operations of an antenna array comprising two or more controllable sections and antenna ports connected to transceiver circuitry. The method includes determining a scenario of transmission or reception by the antenna array, and configuring the transceiver circuitry responsive to the determined scenario. The scenario is defined in terms of a requirement for a number of users intended as receivers or transmitters, respectively, of the transmission or reception and in terms of one or more of: a path loss requirement, a peak rate requirement, and a traffic capacity requirement. The configuration includes, for the transmission or reception, one or more of: allocating a number of sections of the two or more sections of the antenna array and determining a sub-division of the allocated sections, determining a number of information data layers for multiple-input multiple-output application, and allocating a bandwidth.

Antenna array operation control

The invention relates to a method and a system for generating clock signals in a wireless communication device. The method includes generating an uncorrected reference clock signal, generating at least one frequency correction value corresponding to a frequency error in the uncorrected reference clock signal, and generating at least one radio frequency clock signal based on the uncorrected clock signal and the at least one frequency correction value, for receiving and transmitting radio frequency signals. The method further comprise generating, independently of the at least one radio frequency clock signal, a baseband timing signal based on the uncorrected reference clock signal and the at least one frequency correction value, for clocking base-band signal processing circuits.

Clocking scheme for a wireless communication device

A method and apparatus for direct-conversion transmission generates a first frequency signal that is non-harmonically related to a transmit frequency signal, divides the first frequency signal to obtain a mixing frequency signal, divides the first frequency signal to obtain an intermediate frequency reference signal, generates the transmit frequency signal by using the mixing frequency signal to downconvert the transmit frequency signal into an intermediate frequency feedback signal, and phase-locks the intermediate frequency feedback signal to the intermediate frequency reference signal. The transmit frequency signal may be phase modulated, and may serve as an input to a saturated-mode power amplifier that can be configured for corresponding amplitude modulation. Alternatively, the un-modulated transmit frequency signal serves as the carrier signal input to a quadrature modulator, which imparts I/Q modulations to it, thereby producing a modulated carrier signal for input to a linear power amplifier.

Method and apparatus for frequency synthesis in direct-conversion transmitters

A tuning arrangement in a radio receiver includes a front-end circuit having a tunable band-pass filter that is capable of tunably selecting channels within at least one frequency band of an RF signal. A noise source coupled to an input of the tunable band-pass filter introduces a wide-band noise signal into the front-end circuit. A signal detector coupled to an output of the front-end circuit measures at least one signal power associated with a filtered noise signal derived from the wide-band noise signal. A tuning controller, coupled to the tunable band-pass filter by a tuning control signal, adjusts the tuning control signal in response to the at least one measured signal power for tuning the tunable band-pass filter to a desired filter response.

Methods and apparatus for tuning pre-selection filters in radio receivers

A signal source generates a phase-modulated output signal responsive to a phase-modulation signal. A phase splitter splits the phase-modulated output signal into two or more phase-offset output signals. A switch provides a selected one of the phase-offset output signals from the phase splitter to a transmit amplifier circuit. Large phase transitions in the phase-modulation signal are detected and reduced to decrease modulation bandwidth requirements at the signal source. When a phase transition in the phase-modulation signal is reduced, the switch is coherently switched from one phase-offset output signal to another to substantially restore the full phase transition in the output signal presented to the transmit amplifier circuit. In this manner, the transmit amplifier receives substantially the same phase transitions as are in the original phase-modulation signal.

System and method to reduce phase modulation bandwidth

A technique for identifying circuits within an electrical device is disclosed. In one embodiment, additional current sink paths are associated with one or more circuits within the electrical device and measurements of additional current drawn by the current sink paths can be used to identify the associated circuit. In an additional embodiment, a special mode of operation is implemented in the electrical device where the circuit to be identified outputs identity signals in response to control signals from a controller. In a further embodiment, a shift register is activated in the special mode of operation to serially output an identity word in response to the control signals from the controller.

Simple chip identification

The present invention relates to a receiver device comprising a receiver (104) adapted to receive radio signals in two frequency bands (FB1, FB2). The radio signals in one of the frequency bands (FB1) constitute communication signals for a radio system (AMPS, NMT) having a certain channel spacing, whereas the radio signals of the second frequency band (FB2) constitutes communication signals for a second radio system (PCS1900, DCS1800, GSM) having a second certain channel spacing. The receiver (104) comprises two inputs (108, 11) each intended for a radio system having different frequency bands and channel spacing. For radio signals occurring on one input (108), mixing is performed from the RF range directly to the baseband frequency range. For radio signals occurring on the second input (108) the mixing from the radio frequency range to the baseband frequency range is carried out through an intermediate frequency range. Further the receiver (104) comprises an output (112) intended to deliver baseband signals for both radio systems. The output (112) is connected to a baseband unit which is common to the radio systems. In the baseband unit, among other things, lowpass filtering, detection and neighbouring channel suppression are performed on the received radio signal that has been mixed down to the baseband frequency range.

Multi-frequency band receiver for RF signal

A multiple-mode receiver incorporating direct conversion (processing received signals using intermediate frequencies within the same frequency range as the received signal bandwidth) rather than superheterodyne circuitry, allowing receiver hardware components to be re-used rather than replicated for each band. Various embodiments are disclosed in which low pass filters, mixers, quadrature generators, oscillators, and amplifiers are re-used.

Multiple-mode direct conversion receiver

A digitally compensated direct-conversion receiver includes devices for generating digital samples of a base-band in-phase signal and a base-band quadrature signal and for detecting the presence of a second-order product signal produced by an amplitude-modulated interfering signal. Also, the apparatus comprises a device for digitally compensating the digital samples by removing the second-order product signal, thereby producing compensated digital samples. In one method of digitally compensating samples of an information signal quadrature-modulating a carrier signal, estimated samples of a second-order product from a switched carrier signal are formed by averaging the digital samples during two time periods and by determining a time of ramps in the in-phase and quadrature signals that occur between the time periods due to the interfering signal. The digital samples may be differentiated and the results smoothed in determining the time of the ramps. In another apparatus, the estimated samples of the second-order product signal are produced by a device for averaging a square of a difference between respective digital samples of the in-phase signal and the quadrature signal, thereby determining an amplitude of the amplitude-modulated carrier signal, and a device for combining the amplitude and the digital samples, thereby generating the estimated samples.

Digitally compensated direct conversion receiver

A method and a device in a homodyne receiver including a local oscillator generating an oscillator signal at a frequency of f.sub.LO, a mixer, and a reception device for receiving an input signal having a frequency of f.sub.RF, the oscillator signal and the input signal being supplied to the mixer. The oscillator signal is supplied to a first processing unit to produce a first output signal having a frequency of M*f.sub.LO, where M is an integer value. The first output signal is supplied to a second processing unit to produce a second output signal having a frequency of M*f.sub.LO /N=f.sub.LO, where N is an integer number and M.noteq.N, and the mixer and the second processing unit are integrated to minimize leakage of signals being supplied to the mixer from the second processing unit.

Growing community of inventors

Lund, Sweden

Martin Isberg