An input signal is split onto a first data path and a second data path. Values of the input signal above a threshold voltage level are propagated on the second data path and not on the first data path. The propagation of the signal from the input signal terminal through the first data path or the second data path is selectively controlled using two reference bias voltages generated based on a level of the signal.

A method for decreasing multi-path interference, for a vehicle radio receiver including at least two radio reception antennas that each receive a plurality of radio signals composed of time-shifted radio signals resulting from a multi-path effect. The plurality of radio signals combined to deliver a combined radio signal y.sub.s to be played, with: y.sub.n=W.sub.n.sup.T[G.sub.1,n.sup.S, X.sub.1,n+G.sub.2,n.sup.S, X.sub.2,n] at time n, where x.sub.1 and x.sub.2 are vectors the components of which correspond to the plurality of signals received by the first antenna and by the second antenna, respectively, G.sub.1,n.sup.S and G.sub.2,n.sup.S are scalars the components of which are the complex weights of a spatial filter and w.sub.n.sup.T is the transpose matrix of a vector the components of which are the complex weights of a temporal filter. The method includes implementation of an iterative adaptation algorithm to determine the complex weights of the spatial filter and the complex weights of the temporal filter.

A method for decreasing multi-path interference, for the implementation thereof in a vehicle radio receiver including a radio reception antenna that receives a plurality of radio signals corresponding to an emitted radio signal, the plurality of signals received by the antenna being composed of time-shifted radio signals, the plurality of signals being intended to be combined in order to deliver a combined radio signal z.sub.n to be played, with z.sub.n=W.sub.n.sup.TY.sub.n, the method aiming to determine the complex components of the vector of complex weights and including: introducing a temporal correlation, between the real and imaginary parts of the complex weights, that is dependent on the time shift between said received signals, by the expression of the complex weights in polar coordinates, implementing an iterative adaptation algorithm in order to determine the gains and delays of said complex weights able to keep constant over time the modulus of z.sub.n.

A wireless communication apparatus is provided. The wireless communication apparatus includes a denoising circuit configured to receive a noisy complex channel vector(s) in a spatial domain and convert the noisy complex channel vector(s) into a noisy beamspace-domain vector(s) in a beamspace domain. The denoising circuit determines an optimal denoising parameter and denoises the noisy beamspace-domain vector(s) based on the optimal denoising parameter to generate a denoised beamspace-domain vector(s). The denoising circuit then converts the denoised beamspace-domain vector(s) to a denoised complex channel vector(s) in the spatial domain. In examples discussed herein, the denoising circuit determines the optimal denoising parameter and denoises noisy beamspace-domain vector(s) based on a lower-complexity denoising algorithm having reduced computational complexity compared to existing denoising methods, thus helping to enable more accurate channel estimation in the wireless communication apparatus with reduced cost, footprint, and/or power consumption.

Methods and apparatus are disclosed for processing interference due to passive non-linear products of transmitted signals in a wireless network, and more specifically, but not exclusively, to reduction of interference caused to a receiver due to passive intermodulation (PIM) products generated from at least a first Multiple Input Multiple Output (MIMO) signal comprising first and second MIMO component streams at a first carrier frequency. In other scenarios, there may be two or more carrier frequencies combining to cause PIM, and each carrier frequency may have two or more MIMO component streams.

A jamming or MAS system is provided having multiple transmit antennas for transmitting respective transmit signals with spatial diversity to reduce multipath fading. The jamming or MAS communication system communicates with at least one receiver for receiving the transmit signals with no additional processing required at the receiver. In some embodiments, the jamming or MAS communication system includes an associated receiver for receiving and analyzing various signals. The jamming or MAS communication system in the present invention is able to help reduce the effects of multipath fading without modifications to the receiver. Prior art attempts to reduce the effects of multipath fading require some form of additional processing at the receiver. The invention is particularly useful when deployed in a Managed Access Service (MAS) system or a jamming system. In particular, such a system can be used in a facility (such as a prison, school, government building, etc) to prevent cellphone usage.

A discrete-time delay (TD) technique in a baseband receiver array is disclosed for canceling wide modulated bandwidth spatial interference and reducing the Analog-to-Digital Conversion (ADC) dynamic range requirements. In particular, the discrete-time delay (TD) technique first aligns the interference using non-uniform sampled phases followed by uniform cancellation using a cancellation matrix, such as, for example, a Truncated Hadamard Transform implemented with antipodal binary coefficients.

A method for decreasing multi-path interference, for the implementation thereof in a vehicle radio receiver including a radio reception antenna that receives a plurality of radio signals corresponding to an emitted radio signal, the plurality of signals received by the antenna being composed of time-shifted radio signals, the plurality of signals being intended to be combined in order to deliver a combined radio signal z.sub.n to be played, with z.sub.n W.sub.n.sup.TY.sub.n, the method aiming to determine the complex components of the vector of complex weights and including: introducing a temporal correlation, between the real and imaginary parts of the complex weights, that is dependent on the time shift between said received signals, by the expression of the complex weights in polar coordinates, implementing an iterative adaptation algorithm in order to determine the gains and delays of said complex weights able to keep constant over time the modulus of z.sub.n.

A device for processing an audio signal arising from a radiofrequency signal, including: an instantaneous multipath sensor able to analyze the radiofrequency signal so as to determine an instantaneous multipath rate, an instantaneous filter block able to attenuate the audio signal in line with an instantaneous attenuation that is an increasing function of the instantaneous multipath rate, also including a mean multipath sensor able to determine a mean multipath rate, and a mean filter block able to attenuate the audio signal in line with a mean attenuation that is an increasing function of the mean multipath rate. A radio receiver having such a processing device is also disclosed.

Embodiments of the inventive concepts disclosed herein are directed to a system for cancelling interference. The system may include a first antenna and a second antenna spatially separated from the first antenna. The system may include a first time delay unit, coupled to the first antenna, and configured to apply a first time delay and first power gain on a first signal received by the first antenna. The system may include a control circuit, coupled to the first time delay unit, and configured to determine the first time delay and first power gain to cause a modified version of the first signal and a second signal, received by the second antenna, to be aligned in time and power levels.