High-bit-rate digital subscriber line

About: High-bit-rate digital subscriber line is a research topic. Over the lifetime, 516 publications have been published within this topic receiving 8537 citations. The topic is also known as: HDSL & high-bit-rate DSL.

Equal-power coordinated transmission for HDSL

Abstract: In a two-channel transmission system, the signal-to-noise ratio (SNR) at the receiver can in general be different for the channels. Normally, performance will be dominated by the channel with the worst SNR, but it is possible to do much better. The general scheme proposed provides optimum performance when the SNR varies between the channels and/or when the interference is correlated, without varying the transmitted power for each channel. Simplified schemes attain nearly optimum performance under certain channel conditions. >

Method and circuit for simultaneously establishing communication links between a subscriber station and further subscriber stations

Abstract: A method and circuit for simultaneously establishing communication links between a subscriber station connected to a switching center of a communication network via a single subscriber line and other subscriber stations connected to the same communication network wherein, the relevant subscriber line is operated as a multi-channel multiplex line, between the switching center and a translating device which is preferably provided at the transition to another communication network, especially the Internet, a multi-channel multiplex junction line, on the one hand, and, on the other hand, a number of individual junction lines exist, in the translating device, a demultiplexer/multiplexer which is used for the respective transition from a multiplex link to individual connections and conversely is located between the multiplex junction line and the individual junction lines.

EVM Based SNR Estimation Performance in Cross QAM Using Selected Constellation Points

Abstract: In this paper, we investigate the signal to noise ratio (SNR) estimation performance of Cross quadrature amplitude modulation (QAM), which is being used for asymmetric digital subscriber line (ADSL), very high bit rate digital subscriber line (VDSL), and digital video broadcasting - cable (DVB-C), and has been found to be useful in adaptive modulation and blind equalization. At first, the symbol error rate (SER) performance of Cross QAM is analyzed in Rayleigh fading channel. Then we suggest error vector magnitude (EVM) based SNR estimation utilizing the selected constellation points having different types of decision region from one another, and verify that SNR estimation performance of each points have different performance pattern through simulation. From the simulation results, it has been found that when suggested selected constellation points are used for SNR estimation in Cross QAM, estimation performance is enhanced in additive white Gaussian noise (AWGN) channel or Ricean fading channel.

A digital subscriber loop carrier system for providing private line service on multi-party lines

Abstract: To improve multiparty telephone services, a four-channel digital subscriber loop carrier system is proposed. Adaptive differential pulse code modulation bipolar 6-zero substitution line coding, and time-compression multiplexing of speech packets under microprocessor control are novel features of the proposed system. It is believed the design for a digital subscriber loop carrier system outlined will meet the requirements for providing private line service on multiparty lines. The cost of such a system is expected to be less than that required for reinforcement with metallic cables, while providing a comparable level of service. >

Digital telephone subscriber station

Abstract: In a digital telephone subscriber station with a coder filter, an optimum signal-to-noise ratio is achieved for the speech signal to be transmitted by externally timing the DC voltage transformer which powers the coder filter and which is powered via the subscriber connection line with the sampling clock of the coder filter or an integral multiple of the same.