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—In this paper, hardware implementation aspects of the channel estimator in 3GPP LTE terminals are investigated. A channel estimation ASIC, which handles the real-time channel estimation, is presented. Compared to traditional correlator-based channel estimators, the channel estimator presented boosts the throughput at feasible silicon cost by adopting a(More)
In this article, we introduce MATLAB-based link and system level simulation environments for UMTS Long-Term Evolution (LTE). The source codes of both simulators are available under an academic non-commercial use license, allowing researchers full access to standard-compliant simulation environments. Owing to the open source availability, the simulators(More)
—In scenarios with time-varying channels such as intelligent traffic systems or high speed trains, the orthogonality between subcarriers in orthogonal frequency division multiplexing (OFDM) is destroyed leading to inter-carrier interference (ICI). In the literature, ICI equalization algorithms have been proposed; however, they assume perfect channel(More)
—The UMTS Long Term Evolution (LTE) allows the pilot symbol power to be adjusted with respect to that of the data symbols. Such power increase at the pilot symbols results in a more accurate channel estimate, but in turn reduces the amount of power available for the data transmission. In this paper, we derive optimal pilot symbol power allocation based on(More)
—Cellular networks are an essential part of todays communication infrastructure. The ever-increasing demand for higher data-rates calls for a close cooperation between researchers and industry/standardization experts which hardly exists in practice. In this article we give an overview about our efforts in trying to bridge this gap. Our research group(More)
Nowadays, most wireless communication systems employ coherent demodulation on the receiver side. Under this circumstance, part of the available transmission resource is reserved and utilized for channel estimation, referred to as pilot symbols. In recent standards, for example long-term evolution (LTE), a certain adjustment is allowed for the power radiated(More)
—In this paper, we compare the performance of the LTE rate matcher for different code rates when segmentation occurs. We present that, for certain cases of segmentation where the different segments are of dissimilar size, the rate applied to each segment may be different and thus degraded overall performance may occur. We show how a simple method which(More)
—The UMTS Long Term Evolution (LTE) allows the pilot symbol power to be adjusted with respect to that of the data symbols. In this paper, we derive optimal pilot power allocation in multi-cell scenarios under imperfect channel knowledge at the terminals. As cost function, we choose the post-equalization Signal to Interference and Noise Ratio (SINR). We show(More)
—Current Multiple Input Multiple Output (MIMO) Orthogonal Frequency Division Multiplexing (OFDM) based systems for wireless communications enable to adjust power radiated at the pilot symbols. Under time-invariant channels, a power increase at the pilot symbols results in improved quality of the channel estimate. However, under time-variant channels, this(More)