IQ mismatch correction for analog chain IQ mismatch impairments is based on a two-filter architecture. In either RX or TX, an IQmc mismatch corrector (digital chain) filters I and Q digital signals, and includes an I-path to receive the I signal, and a Q-path to receive the Q signal, and is configured with two filters: an in-path filter to filter either the I signal or the Q signal received in the same path; and a cross-path filter to filter either the I signal or the Q signal received in the other path. The IQmc mismatch corrector can include: an I-path delay element to provide a delay to the I signal corresponding to a delay through either the in-path filter or the cross-path filter; and a Q-path delay element to provide a delay to the Q signal corresponding to a delay through either the in-path filter or the cross-path filter.

Device under test (DUT) interface device for use in a system for executing measurements on a device under test (9) with a vector network analyser (11).

The DUT interface device comprises a divider/coupler component (4), a variable gain amplifier (5), an I/Q mixer (6) and a bridge/coupler component (7) and provides a test signal (a) to the DUT terminal (3).

The system further comprises a control unit (12) connected to the vector network analyser (11) and to control input terminals (8) of associated ones of the at least one DUT interface device (1). The control unit (12) provides quadrature control signals (V.sub.I, V.sub.Q) for the associated at least one DUT interface device (1), which are connected directly to the device under test (9). The present invention further relates to proper calibration and measurement methods.

Method of operating electronic device including transmitter and receiver in wireless communication system and the electronic device are provided. The method includes acquiring signal passing through intermediate path between transmitter and receiver; estimating phase change in intermediate path, based on the signal and a reception signal predicted by a modeled system; and determining in-phase/quadrature (I/Q) mismatch parameters indicating a mismatch of I components and Q components of the transmitter and the receiver from the phase change. The electronic device includes a transmitter; a receiver; and at least one processor, configured to acquire a signal passing through an intermediate path between the transmitter and the receiver, estimate a phase change in the intermediate path, based on the signal and a reception signal predicted by a modeled system, and determine I/Q mismatch parameters indicating a mismatch of I components and Q components of the transmitter and the receiver from the phase change.

A method for providing IQ mismatch (IQMM) compensation includes: sending a single tone signal at an original frequency; determining a first response of an impaired signal at the original frequency and a second response of the impaired signal at a corresponding image frequency; determining an estimate of a frequency response of the compensation filter at the original frequency based on the first response and the second response; repeating the steps of sending the single tone signal, determining the first response and the second response, and determining the estimate of the frequency response of the compensation filter by sweeping the single tone signal at a plurality of steps to determine a snapshot of the frequency response of the compensation filter; converting the frequency response of the compensation filter to a plurality of time-domain filter taps of the compensation filter by performing a pseudo-inverse of a time-to-frequency conversion matrix; and determining a time delay that provides a minimal LSE for the corresponding time domain filter taps.

Wide band quadrature signal generation includes a frequency synthesizer generating a LO or 2LO signal, a polyphase filter coupled to receive the LO signal and generate first in-phase and quadrature LO signals, a 2:1 frequency divider coupled to receive the 2LO signal and generate second in-phase and quadrature LO signals, and a LO signal selector for selecting either the first or second in-phase LO signals as an output in-phase LO signal and either the first or second quadrature LO signals as an output quadrature LO signal based on an output frequency. In some embodiments, when the output frequency is above a threshold, the first in-phase and quadrature LO signals are selected as the output in-phase and quadrature LO signals and when the output frequency is at or below the threshold, the second in-phase and quadrature LO signals are selected as the output in-phase and quadrature LO signals.

A system having a set of common hardware and common signal processing together with a common waveform family that can be used to achieve both efficient radar and efficient communications functions. The system includes a common radar/communications transmitter having a transmission antenna and a combined radar and communications receiver having a common reception antenna. The common radar/communications transmitter is configured to transmit combined radar/communications waveform-modulated signals comprising symbols, each symbol consisting of an up chirp and a down chirp. The combined radar and communications receiver includes a baseband radar signal processing module configured to estimate range and range rate of a radar object from the received symbols and a baseband communications signal processing module configured to detect slopes and initial phases of the up and down chirps of each received symbol.

A local oscillator outputs a local oscillation signal. A orthogonal detector subjects a received signal to orthogonal detection by using the local oscillation signal so as to output an I-phase baseband signal and a Q-phase baseband signal. A first HPF and a second HPF reduce a direct current component of each of the I-phase baseband signal and the Q-phase baseband signal. A demodulator demodulates the I-phase baseband signal and the Q-phase baseband signal output from the first HPF and the second HPF. A distribution detector detects an unevenness in a distribution of the I-phase baseband signal and the Q-phase baseband signal with the reduced direct current component. When the distribution detector detects an unevenness in the distribution, the distribution detector changes a status of the first HPF and the second HPF.

A method of providing wireless communications in a wireless network can include wirelessly receiving a chirp spread-spectrum modulated signal at a first gateway device, the chirp spread-spectrum modulated signal being transmitted by a remote client device. The chirp spread-spectrum modulated signal can be demodulated at the first gateway device to provide demodulated data at the first gateway device. The demodulated data can be processed to provide an indication that a decode of a packet including the demodulated data failed. Time adjacent chirps included in the demodulated data can be combined to provide combined data at the first gateway device. A message can be transmitted from the first gateway device to a remote server responsive to an amplitude of the combined data exceeding a threshold value and the indication that the decode of the packet including the demodulated data failed.

The invention described herein is directed to different embodiments of a wireless communications device that can be used in many different applications, such as but not limited to a digital oversampling receiver adapted to select desired signals and to reject undesired signals. In one embodiment, a wireless communications device is disclosed that comprises an architecture for a receiver front end that obviates the need for high order passive circuitry or RC active circuitry to select desired signals and to reject undesired signals.

A method for providing IQ mismatch (IQMM) compensation includes: sending a single tone signal at an original frequency; determining a first response of an impaired signal at the original frequency and a second response of the impaired signal at a corresponding image frequency; determining an estimate of a frequency response of the compensation filter at the original frequency based on the first response and the second response; repeating the steps of sending the single tone signal, determining the first response and the second response, and determining the estimate of the frequency response of the compensation filter by sweeping the single tone signal at a plurality of steps to determine a snapshot of the frequency response of the compensation filter; converting the frequency response of the compensation filter to a plurality of time-domain filter taps of the compensation filter by performing a pseudo-inverse of a time-to-frequency conversion matrix; and determining a time delay that provides a minimal LSE for the corresponding time domain filter taps.