The main emphasis in modern RF power amplifier (PA) research is on improving linearity while at the same time maintaining reasonably good efficiency, for which purpose external linearization in the form of feedforward or predistortion is often used. Linearity and linearization can be considered from both a fundamental signal (amplitude and phase conversions, AM-AM & AM-PM) and an intermodulatio...

Achiral supramolecular hydrogen bonded complexes between rod-like 4-(4-alkoxyphenylazo)pyridines and a taper shaped 4-substituted benzoic acid form achiral (Ia3[combining macron]d) and chiral "Im3[combining macron]m-type" bicontinuous cubic (I432) phases and a chiral isotropic liquid mesophase (Iso1[*]). The chiral phases, resulting from spontaneous mirror symmetry breaking, represent conglomer...

The design of a fully integrated upconversion mixer for use in a UMTS transmitter is presented. UMTS is the system which is developped for wireless transmission with high datarates. It uses Code Division Multiple Access to separate users of the same channel at the same time. The transmitted signal of one user has a nonconstant envelope due to filtering that is applied to limit the bandwidth. In...

In future full-duplex communications, the cancellation of self-interference (SI) arising from hardware nonidealities, will play an important role in the design of mobilescale devices. To this end, we introduce an optimal digital SI cancellation solution for shared-antenna-based direct-conversion transceivers (DCTs). To establish that the underlying widely linear signal model is not adequate for...

Multi-carrier code division multiple access (MC-CDMA) is a powerful modulation technique that is being considered in many emerging broadband communication systems. It exploits the advantages of spread spectrum and the advantages of multi-carrier systems, particularly orthogonal frequency division multiplexing (OFDM) technique. However, since it uses OFDM, the MC-CDMA signals are a superposition...

background and objectives: surgical cancelation is a significant source of time and resource waste, patientsafety risk, and stress for patients and their families. in this study, a risk management-based approach is developed to prioritize factors contributing to surgical cancellation. methods: factors leading to surgical cancellation were comprehensively classified based on literature review.a...

We propose a multichannel residual cross-talk cancellation strategy to operate in environments where each microphone signal is dominated by one of several simultaneously active sound sources, like in a call-center scenario. The method relies on a two-step adaptive filtering scheme derived from an established GSC structure. The filter updates are performed in the frequency domain to allow an eff...

In this paper, we propose a novel adaptive beamforming algorithm with low signal distortion capability and high computational efficiency. The proposed algorithm incorporates the crosstalk-resistant adaptive noise canceller (CTRANC) in place of the usual adaptive interference canceller (AIC). Doing so, a better signal leakage estimate is provided at the adaptive interference canceller input but ...

In this paper, the relation between hlock digital filtering and quadrature mirror filter (QMF) hanks is explored. Necessary and sufficient conditions for alias cancellation in QMF hanks are expressed in terms of an associated matrix, derived from the polyphase components of the analysis and synthesis filters. These conditions, called the pseudocirculant conditions, enahle us to directly unite Q...