Jens Baltersee

• Doctor of Philosophy
• Patent Examiner at European Patent Office (EPO) Netherlands

The constrained capacity of a coherent coded modulation (CM) digital communication system with data-aided channel estimation and a discrete, equiprobable symbol alphabet is derived under the assumption that the system operates on a flat fading channel and uses an interleaver to combat the bursty nature of the channel. It is shown that linear minimu...

This paper deals with the problem of channel tracking for RAKE receivers in propagation environments characterized by closely spaced multipath components. After outlining why conventional single-path channel tracking algorithms fail in such scenarios, several new estimation algorithms are developed that are tailored to channels with closely spaced...

The achievable rate of a coherent coded modulation digital communication system with data-aided channel estimation and a discrete equiprobable symbol alphabet is derived under the assumption that the system operates on a flat fading multiple-input/multiple-output channel and uses a perfect interleaver to combat the bursty nature of the channel. It...

RAKE receivers for DS-CDMA communications over fading channels require the knowledge of instantaneous complex channel phasors for each of the multipath diversity branches (or RAKE fingers). If transmit diversity is employed by using N transmit antennas in the basestation, N such fading channels need to be estimated in the mobile receiver. In this p...

A new adaptive timing error detector (TED) embedded in a code-tracking loop for RAKE reception of directsequence -CDMA signals is presented. The loop consists of a digital coherent TED and a loop filter with lowpass characteristic. In a multipath fading environment, one such loop can be allocated for each finger in a RAKE receiver and the interfere...

An extension to the timing error detector (TED) for timing/code tracking loops used inside RAKE receivers in CDMA systems is presented. In contrast to the conventional TED it is well suited for the case of multipath propagation channels. In order to accomplish this task, the conventional early-late TED is replaced by an FIR filter which is optimize...

The performances of phasor estimation algorithms for the UMTS RAKE Receiver are analysed. Due to the need of covering a wide range of possible mobile speeds and spreading factors, two different algorithms are considered here, namely a LMS-Kalman type algorithm, and a Wiener filter. The Wiener filter is considered both, as a predictor and a smother....

A new coherent timing error detector (TED) for timing/code tracking loops used inside RAKE receivers in CDMA systems is presented. In contrast to the conventional TED it is well suited for the case of multipath propagation channels. In order to accomplish this task a compensation term is introduced inside the tracking loop directly behind the conve...

A novel channel estimation scheme is proposed for a RAKE receiver operating in the downlink of a mobile communication scenario. The approach is an extension of the well known Wiener channel estimator and partly cancels multipath interference, with the additional advantage of being able to cope with physically closely spaced multipaths which arise,...

A fast simulation technique for the analysis of the system performance of digital receivers is presented and applied to the UMTS terrestrial radio access (UTRA). This semianalytical method comprises the computation of receiver output statistics, conditioned on a static channel model, a given spreading sequence and a given transmitted symbol sequenc...

A novel channel estimation scheme is proposed for a RAKE receiver operating in the downlink of a mobile communication scenario. The approach is an extension of the well known Wiener channel estimator and partly cancels multipath interference, with the additional advantage of being able to cope with physically closely spaced multipaths which arise,...

RAKE receivers for DS-CDMA communications over fading channels require the knowledge of instantaneous complex channel phasors for each of the multipath diversity branches (or RAKE fingers). If transmit diversity is employed by using N transmit antennas in the basestation, N such fading channels need to be estimated in the mobile receiver. A channel...

An extension to the timing error detector (TED) for timing/code tracking loops used inside RAKE receivers in CDMA systems is presented. In contrast to the conventional TED, it is well suited for the case of multipath propagation channels. In order to accomplish this task, the conventional early-late TED is replaced by an FIR filter which is optimiz...

The achievable rate of a coherent coded modulation (CM) digital communication system with data-aided channel estimation and a discrete, equiprobable symbol alphabet is derived under the assumption that the system operates on a flat fading MIMO channel and uses an interleaver to combat the bursty nature of the channel. It is shown that linear minimu...

A new adaptive timing error detector (TED) embedded in a code-tracking loop for RAKE reception of direct sequence-CDMA signals is presented. The loop consists of a digital coherent TED and a loop filter with lowpass characteristic. In a multipath fading environment, one such loop can be allocated for each finger in a RAKE receiver and the interfere...

A new coherent timing error detector (TED) for timing/code tracking loops used inside RAKE receivers in CDMA systems is presented. In contrast to the conventional TED it is well suited for the case of multipath propagation channels. In order to accomplish this task a compensation term is introduced inside the tracking loop directly behind the conve...

this report. Exceptions are the methods titled 'Conventional Methods'. This Section of the report gives an overview about the different signal processing methods that are used in the Uplink. Current research trends are indicated and papers are cited in which the different signal processing methods are used. Note, that the LTV filters in the pattern...

The performance of phasor estimation algorithms for the UMTS RAKE receiver are analysed. Due to the need of covering a wide range of possible mobile speeds and spreading factors, two different algorithms are considered, namely a LMS-Kalman type algorithm, and a Wiener filter. The Wiener filter is considered both, as a predictor and a smother. It is...

Performance bounds for a UMTS RAKE receiver with imperfect timing synchronisation are presented. Firstly, an analytical expression for the bit error probability (P_e) performance of the RAKE receiver is derived. This analysis establishes that the bit error probability performance of the RAKE receiver is less sensitive to timing errors for...

This paper addresses performance analysis and optimization of receive filters in a GSM system using an MLSE detection algorithm. In order to include the effects of adjacent and co-channel interference on the sequence estimation, appropriate signal models are derived. These models are used to calculate a performance measure for a system operating un...

A new channel estimation algorithm capable of exploiting a-priori knowledge about modulation and receive filters and the power delay profile of the physical channel is presented. In order to incorporate the a-priori knowledge into the linear minimum mean square error (LMMSE) channel estimator, a Bayesian approach is applied to an appropriate GSM sy...

A fast simulation technique for the analysis of the system performance of digital receivers is presented and applied to the UMTS terrestrial radio access (UTRA). This semianalytical method comprises the computation of receiver output statistics, conditioned on a static channel model, a given spreading sequence and a given transmitted symbol sequenc...

A statistical channel model for fading channels is presented that is applicable for the simulation and design of communication systems with multiple (smart) antennas: Firstly, the continuous time vector channel model is developed starting from the fundamental wave equation in free space. This continous time channel model is then used to derive a T/...

New learning algorithms for an adaptive nonlinear forward predictor that is based on a pipelined recurrent neural network (PRNN) are presented. A computationally efficient gradient descent (GD) learning algorithm, together with a novel extended recursive least squares (ERLS) learning algorithm, are proposed. Simulation studies based on three speech...

A novel linearised Recursive Least Squares (LRLS) learning algorithm is presented for an adaptive non-linear forward predictor based on a Pipelined Recurrent Neural Network (PRNN). Simulation studies with speech signals show that the non-linear predictor does not perform satisfactorily when the previously proposed stochastic gradient (SG) algorithm...

New learning algorithms for an adaptive nonlinear forward predictor which is based on a pipelined recurrent neural network are presented. A computationally efficient gradient descent algorithm, as well as a novel Extended Recursive Least Squares (ERLS) algorithm are tested on the predictor. Simulation studies, based on three speech signals, which h...