Abstract: A technique for generating a radio frequency signal (302) based on a baseband signal (304) is provided. As to a method aspect of the technique, an amplitude signal (r) and a phase signal (?) depending on the baseband signal (304) are provided. The phase signal is modulated to a carrier frequency. As to another method aspect of the technique, a baseband signal (304) is modified by adding an offset signal to the baseband signal (304). The offset signal prevents the modified baseband signal (316) from entering a first signal region. An amplitude signal (r) and a phase signal (?) is provided based on the modified baseband signal (316). The phase signal (?) is modulated to a carrier frequency (?c). The modulated phase signal (?) is amplified according to the amplitude signal (r) to generate a preliminary radio frequency signal (318).

Abstract: In one aspect, the present invention exploits the termination conductances of a time-discrete harmonic mixer as another degree of freedom in configuring the mixer to meet given harmonic rejection performance requirements while using reduced number of unit cells. The values of these termination conductances are purposefully configured to introduce a desired non-linearity in quantization of the mixer transconductance by the unit cells. The non-uniform quantization produces a non-linear fitting of the transconductance levels to the transconductance points defining the target sinusoidal waveform. As a consequence of its termination conductance configuration, the contemplated mixer achieves levels of harmonic rejection with that would not be met if the reduced number of unit cells operated with uniform quantization. As a further advantage, the manipulated conductance values generally are lower than those used in conventional designs, e.g.

Abstract: A radio circuit comprises an interface unit for communicating data and commands over a communication link between a digital baseband circuit and the radio circuit. Furthermore, the radio circuit comprises an event-scheduling unit, a local time-reference unit, a synchronization unit, and an execution-control unit. The event-scheduling unit is arranged to receive event-request commands specifying an event to be executed in the radio circuit and a time instant at which the specified event is to be executed, from the digital baseband circuit. Furthermore, the event-scheduling unit is arranged to, in response to receiving an event request-command, schedule the specified event to be executed on the specified time instant. The execution-control unit is arranged to issue execution of each scheduled event at the scheduled time instant based on time information from the local time reference unit.

Abstract: A user equipment (UE) in a communication system can keep track of the cell/frequency deployment of a network operator preferred by the user, and based on the tracked information, the UE can build up its own user-specific Neighbor Cell List. When the UE is roaming, the UE does received-signal measurements according to cells and carrier frequencies identified in the broadcast Neighbor Cell Lists of the roamed-into network, but the UE also does received-signal measurements (with higher priority) according to the user-specific Neighbor Cell List that it has built up. Accordingly, a UE implementing a user-specific Neighbor Cell List analyzes its radio environment based on received signals and stores information about that environment, including user-preference information that prioritizes cells in the radio environment. The UE can then carry out cell search based on the stored environment and user-preference information.

Abstract: A processing device processes an analog complex input signal representing a sequence of OFDM symbols in a radio-receiver. The processing device comprises processing paths, each comprising a complex mixer and an analog channel-selection filter. Furthermore, the processing device comprises an oscillator unit that provides local oscillator signals associated with the complex mixer of each processing path. A control unit determines, based on received control data, subcarrier locations, within at least one individual OFDM symbol of the sequence, of one or more resource blocks allocated to the radio receiver. The control unit, for each of the at least one individual OFDM symbol, controls the local oscillator signals based on the determined subcarrier locations and passbands of the channel-selection filters such that each resource block allocated to the radio receiver is frequency translated by a complex mixer of the processing paths to appear within the passband of the following channel-selection filter.

Abstract: A radio-receiver circuit. The radio receiver circuit comprises an analog-to-digital conversion unit. The analog-to-digital conversion unit comprises an analog-to-digital converter, ADC, and a filter operatively connected to an input terminal of the ADC in a receive path of the radio-receiver circuit. The radio-receiver circuit further comprises a control unit adapted to receive control data and determine, based on the control data, a frequency band in which data is to be transmitted to the radio-receiver circuit during a subsequent time interval. Furthermore, the control unit is adapted to adapt at least one frequency characteristic of the analog-to-digital conversion unit to the determined frequency band for receiving said data transmitted in said subsequent time interval.

Abstract: Efficient carrier aggregation is enabled in a receiver employing a single frequency source, and dividing the frequency source by different frequency dividing factors to generate two or more RF LO frequencies. Received signals are down-converted to intermediate frequencies by mixing with the respective RF LO frequencies. By utilizing only a single high frequency source, embodiments of the present invention avoid spurious and injection locking issues that arise when integrating two or more frequency sources, and additionally reduce power consumption as compared to a multiple frequency source solution.

Abstract: A relay node (34) which wirelessly communicates on a backhaul link over a first interface with a base station node (28) of a radio access technology network and which wirelessly communicates on an access link over a second interface with a wireless terminal (30). The relay node (34) comprises a transceiver (36) and a duplexer section (40). The transceiver (36) comprises a transmitter (42) and a receiver (44). The duplexer section (40) comprises plural transceiver ports (50, 52) and at least one antenna port (48). The relay node (34) is configured to provide a transmit signal from the transmitter (42) in a manner whereby a backhaul link portion of the transmit signal is conveyed through a different transceiver port (50) of the duplexer section than is an access link portion of the transmit signal.

Abstract: In one aspect, the present invention exploits the termination conductances of a time-discrete harmonic mixer as another degree of freedom in configuring the mixer to meet given harmonic rejection performance requirements while using reduced number of unit cells. The values of these termination conductances are purposefully configured to introduce a desired non-linearity in quantization of the mixer transconductance by the unit cells. The non-uniform quantization produces a non-linear fitting of the transconductance levels to the transconductance points defining the target sinusoidal waveform. As a consequence of its termination conductance configuration, the contemplated mixer achieves levels of harmonic rejection with that would not be met if the reduced number of unit cells operated with uniform quantization. As a further advantage, the manipulated conductance values generally are lower than those used in conventional designs, e.g.

Abstract: A technique for controlling suppression of self-interference in a relay node configured to transmit and receive simultaneously using the same frequency channel or using proximate frequency channels is provided. A method implementation of this technique comprises the steps of actively cancelling a signal transmitted from the relay node that leaks back into a receiver of the relay node to suppress self-interference, determining whether an increase of an amount of self-interference suppression is needed or whether self-interference suppression can be decreased, and increasing or decreasing, depending on the result of the determination, at least one of the transmit power of the signal transmitted from the relay node and the receive power of the relay node.

Abstract: A technique for self-interference suppression control for a relay node is provided. The relay node comprises a transmitter and a receiver, and is adapted to transmit and received simultaneously using the same frequency channel or using proximate frequency channels. The relay node further comprises an interference signal estimator having a first input adapted to receive a transmitter signal from the transmitter, a second input adapted to receive adaptation metric and an output adapted to output an estimated interference signal generated by the interference signal estimator based on the transmitter signal and the adaptation metric. A subtractor is coupled to the output of interference signal estimator and configured to subtract the estimated interference signal from a received signal in the receiver so as to actively cancel a signal transmitted from the relay node that leaks back into the receiver of the relay node to suppress self-interference.

Abstract: Methods and a receiver of positioning a spurious signal for reducing the impact of the spurious signal on a received Orthogonal Frequency Division Multiplexing, OFDM signal, are presented. The method comprises determining the frequency of a spurious signal (steps 102, 204, 404), determining the frequency for the respective sub-carrier of the OFDM signal and the difference between the frequency of a sub-carrier and the frequency of a spurious signal (steps 104, 206, 406), and adjusting at least one of: the frequency of the first oscillator (step 208) and a parameter related to the frequency of a second oscillator, to decrease the frequency difference between a sub-carrier and a spurious signal (steps 106, 212, 408). By positioning a spurious signal at or near a sub-carrier frequency, the performance impact of the spurious signal is reduced, and the receiver performance improved.

Abstract: A radio circuit comprises an interface unit for communicating data and commands over a communication link between a digital baseband circuit and the radio circuit. Furthermore, the radio circuit comprises an event-scheduling unit, a local time-reference unit, a synchronization unit, and an execution-control unit. The event-scheduling unit is arranged to receive event-request commands specifying an event to be executed in the radio circuit and a time instant at which the specified event is to be executed, from the digital baseband circuit. Furthermore, the event-scheduling unit is arranged to, in response to receiving an event request-command, schedule the specified event to be executed on the specified time instant. The execution-control unit is arranged to issue execution of each scheduled event at the scheduled time instant based on time information from the local time reference unit.

Abstract: The invention proposes a way of inserting an analog test signal during normal reception into analog blocks of an OFDM receiver in such a way that the reception is either not corrupted at all, or only very little. This is achieved either by inserting the analog test signal in time or frequency where it does not corrupt the received signal, or by accounting for the interfering analog test signal in the decoding process.

Abstract: A processing device (40) for processing an analog complex input signal generated by downconversion of an aggregated-spectrum radio-frequency signal in a radio-receiver (10), wherein the complex input signal comprises a plurality of sub bands (S1-S4) scattered across a total frequency band (4) of the complex input signal. The processing device (40) comprises a plurality of processing paths (P1-PN). wherein each processing path (P1-PN) is adapted to process an associated sub band (S1-S4). Each processing path comprises a complex mixer (CM1-CMN) adapted to frequency translate the complex input signal, and an analog channel-selection filter (CSF1-CSFN) arranged to filter an output signal of the complex mixer (CM1-CMN) and pass the frequency translated associated sub band (S1-S4). A control unit (60) is adapted to receive control data indicating frequency locations of the sub bands (S1-S4) and, for each processing path (P1-PN).

Abstract: In a dual-carrier, double-conversion Orthogonal Frequency Division Multiplexing (OFDM) receiver a frequency synthesizer generates a first local oscillator signal for the first down-conversions stage of the receiver. A frequency divider is used to derive a second local oscillator signal from the first local oscillator signal, thus eliminating the need for a separate frequency synthesizer for the second down-conversion stage. A controller determines the frequency of the first local oscillator signal and a divisor M to align subcarrier grids for said first and second baseband signals with DC.

Abstract: The invention relates to a complex intermediate frequency (CIF) mixer stage, methods of operation thereof, and methods of calibration thereof. The CIF mixer stage comprises numerous individual mixers driven by IF clock signals to down-convert received IF signals into a set of signals at baseband frequency which are further combined to form a lower side band signal and an upper side band signal. The IF clock signals used have a predefined phase relationship among them, which involves tunable phase skews. By calibration of the conversion gains and the phases of the IF clock signals the gain and phase imbalance introduced in a preceding radio frequency mixer stage and/or the CIF mixer stage can be cancelled. Further, in-channel IQ leakage control can be applied to the lower side band signal and/or the upper side band signal. The CIF mixer stage can thus effectively suppress image interference and IQ leakage.

Abstract: A complex intermediate frequency mixer (IFM) for frequency translating a received complex intermediate frequency, IF, signal, wherein the received complex IF signal comprises at least two frequency bands located at upper-side and lower-side of 0 Hz, is provided. The complex intermediate frequency mixer comprises a first, second, third and fourth mixer (M1, M2, M3, M4). The complex intermediate frequency mixer further comprises a first, second, third and fourth gain adjusting component (?1, ?2, ?2, ?1), connected to a first, second, third and fourth mixer output (M1-out, M2-out, M3-out, M4-out), respectively. Moreover, a first summing unit (S1), connected to a first gain output (?1-out), a fourth gain output (?1-out) and a third mixer output (M3-out) negated, and second summing unit (S2), connected to the second gain output (?2-out), the third gain output (?2-out) and the fourth mixer output (M4-out), are configured to output a first baseband complex signal of the received complex IF signal.

Abstract: A radio-receiver circuit having an analog-to-digital conversion unit. The analog-to-digital conversion unit comprises an analog-to-digital converter (ADC), and a filter operatively connected to an input terminal of the ADC in a receive path of the radio-receiver circuit. The radio-receiver circuit further comprises a control unit adapted to receive control data and determine, based on the control data, a frequency band in which data is to be transmitted to the radio-receiver circuit during a subsequent time interval. Furthermore, the control unit is operative to adapt at least one frequency characteristic of the analog-to-digital conversion unit to the determined frequency band for receiving said data transmitted in said subsequent time interval.

Abstract: A conversion circuit (20) for converting a complex analog input signal having an in-phase, I, component and a quadrature-phase, Q, component resulting from frequency down conversion of a radio-frequency, RF, signal (XRF) to a frequency band covering 0 Hz into a digital representation is disclosed. It comprises a channel-selection filter unit (40) arranged to filter the complex analog input signal, thereby generating a channel-filtered I and Q components, and one or more processing units (53, 53a-b). Each processing unit comprises four mixers (60-75) for generating a first and a second frequency-translated I component and a first and a second channel-filtered Q component based on two LO signals with equal LO frequency and a 90° mutual phase shift. Furthermore, each processing unit comprises a combiner unit (85, 120) for generating a first, a second, a third, and a fourth combined signal proportional to sums and differences between said frequency translated I and Q components.