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An iterative decoding threshold analysis for terminated regular LDPC convolutional (LDPCC) codes is presented. Using density evolution techniques, the convergence behavior of an iterative belief propagation decoder is analyzed for the binary erasure channel and the AWGN channel with binary inputs. It is shown that for a terminated LDPCC code ensemble, the thresholds are better than for correspondi
Massive MIMO, also known as very-large MIMO or large-scale antenna systems, is a new technique that potentially can offer large network capacities in multi-user scenarios. With a massive MIMO system, we consider the case where a base station equipped with a large number of antenna elements simultaneously serves multiple single-antenna users in the same time-frequency resource. So far, investigatio
Consider the communication system model y = HFx+n, where H and F are the channel and precoder matrices, x is a vector of data symbols drawn from some lattice-type constellation, such as M-QAM, n is an additive white Gaussian noise vector and y is the received vector. It is assumed that both the transmitter and the receiver have perfect knowledge of the channel matrix H and that the transmitted sig
TV-on-Demand services have become one of the most popular Internet applications that continuously attracts high user interest. With rapidly increasing user demands, the existing network conditions may not be able to ensure a low start-up delay of video playback. Prefetching has been broadly investigated to cope with the start-up latency problem, which is also known as user perceived latency. In th
This paper presents class-D CMOS oscillators capable of an excellent phase noise performance from a very low power supply voltage. Starting from the recognition of the time-variant nature of the class-D LC tank, accurate expressions of the oscillation frequency, oscillation amplitude, current consumption, phase noise, and figure-of-merit (FoM) have been derived. Compared with the commonly used cla
This paper presents a wideband CMOS power amplifier intended for cellular handset applications. The circuit exploits injection locking to achieve a power gain of 20.5dB from a single stage amplifier. The maximum output power of 29dBm, with a peak drain- and power-added-efficiency (PAE) of 66% and 64%, respectively, occurs at a center frequency of 2GHz with a 3V supply. A cross-coupled cascode topo
The performance of continuous time deltasigma modulators is limited by their large sensitivity to feedback pulse-width variations caused by clock jitter in their feedback DACs. To mitigate that effect, a dual switched- capacitor-resistor feedback DAC technique is proposed. The architecture has the additional benefit of reducing the typically high switched-capacitor-resistor DAC output peak current
Context: In large software organizations with a product line development approach, system test planning and scope selection is a complex task. Due to repeated testing: across different testing levels, over time (test for regression) as well as of different variants, the risk of redundant testing is large as well as the risk of overlooking important tests, hidden by the huge amount of possible test
This paper presents an iterative decoder for faster-than-Nyquist (FTN) and orthogonal signaling multi-carrier systems. FTN signaling is a method of improving bandwidth efficiency at the expense of higher processing complexity in the transceiver. The decoder can switch between orthogonal and FTN signaling modes and exploits channel properties to improve bandwidth efficiency. The decoder is fabricat
It has been postulated that six co-located orthogonally polarized electrical and magnetic dipoles can offer up to six degrees of freedom (DOFs) in a multipath scattering environment. In other words, a six-fold increase in channel capacity can be achieved in the context of MIMO systems. However, due to the complexity in designing and measuring such a six-port antenna, to our knowledge, no experimen
Frequency multiplication by 3/2 is proposed as a means to expand the frequency generation capabilities of a single LC VCO. Fractional frequency multiplication is obtained by cascading a broadband injection locked modulo-two divider and a multiply-by-three circuit based on edge combining. The proposed solution is inductorless, thus very compact. It allows the generation of all frequencies from 2.7
Context: Scope management is a core part of software release management and often a key factor in releasing successful software products to the market. In a market-driven case, when only a few requirements are known a priori, the risk of overscoping may increase. Objective: This paper reports on findings from a case study aimed at understanding overscoping in large-scale, market-driven software dev
Reference attribute grammars (RAGs) have proven practical for gen- erating production-quality compilers from declarative descriptions, as demonstrated by the JastAdd system. Recent results indicate their applicability also to generating semantic services in interactive editors. For use in editors, it is necessary to update the attribution after edit operations. Earlier algorithms based on statical
The design of multiple antennas in compact mobile terminals is a significant challenge, due to both practical and fundamental design tradeoffs. In this paper, fundamental antenna design tradeoffs of multiple antenna terminals are presented in the framework of characteristic mode analysis. In particular, interactions between the antenna elements and the characteristic modes and their impact on desi
