Twisted-pair Copper Cables Research Articles

Twisted Pair Cable Fault Diagnosis via Random Forest Machine Learning

Applying the fault diagnosis techniques to twisted pair copper cable is beneficial to improve the stability and reliability of internet access in Digital Subscriber Line (DSL) Access Network System. The network performance depends on the occurrence of cable fault along the copper cable. Currently, most of the telecommunication providers monitor the network performance degradation hence troubleshoot the present of the fault by using commercial test gear on-site, which may be resolved using data analytics and machine learning algorithm. This paper presents a fault diagnosis method for twisted pair cable fault detection based on knowledge-based and data-driven machine learning methods. The DSL Access Network is emulated in the laboratory to accommodate VDSL2 Technology with various types of cable fault along the cable distance between 100 m to 1200 m. Firstly, the line operation parameters and loop line testing parameters are collected and used to analyze. Secondly, the feature transformation, a knowledge-based method, is utilized to pre-process the fault data. Then, the random forests algorithms (RFs), a data-driven method, are adopted to train the fault diagnosis classifier and regression algorithm with the processed fault data. Finally, the proposed fault diagnosis method is used to detect and locate the cable fault in the DSL Access Network System. The results show that the cable fault detection has an accuracy of more than 97%, with less minimum absolute error in cable fault localization of less than 11%. The proposed algorithm may assist the telecommunication service provider to initiate automated cable faults identification and troubleshooting in the DSL Access Network System.

Measurement and causal modelling of twisted pair copper cables

Measurement and causal modelling of twisted pair copper cables

Impact of twisting rate in 10 pairs of unshielded twisted-pair copper cables on insertion loss and crosstalk coupling for G.fast technology

An ultrafast digital subscriber line (DSL) technology called G.fast is important for ultrafast broadband Internet access services. In G.fast, the existing cable bundles installed for 250 m from the distribution point to the customer’s premises are used to support the gigabit data transmission (aggregated 1 Gbit/s) for frequency up to 106 MHz or 212 MHz. Since unshielded cable is used, and the frequency is 12 times higher compared to the very high-speed DSL2 (VDSL2), it is important to investigate the cable performance in terms of insertion loss and crosstalk coupling. In this paper, the impact of cable twisting rate on 10 pairs of unshielded twisted-pair copper cables for a small copper bundle on insertion loss and crosstalk coupling is investigated. A simulation model is developed based on the standard cable installed in Malaysia. The model reliability is validated by comparing the obtained result with the published result in the literature. Besides, the twisting rate of 100 m cable is manipulated by changing its lay size to determine its impact on insertion loss and crosstalk coupling. The results showed that a high twisting rate can reduce the far-end crosstalk but increase both the insertion loss and near-end crosstalk.

Spatial correlation of alien crosstalk in MIMO DSL systems

We statistically characterize the spatial correlation of measured far-end crosstalk collected on 2 kft of 26 AWG twisted-pair copper cable. We then develop and verify a parameterized model of this spatial correlation and use it to investigate the behavior of the spatial correlation of far-end crosstalk in a twisted-pair environment.

Monte Carlo FEXT cancellers for DSL channels

Crosstalk coupling is a severe impairment to transmission on twisted-pair copper cables such as digital subscriber telephone loops (DSLs). In this paper, we investigate the problem of far-end crosstalk (FEXT) cancellation for DSL. We propose a new soft interference canceller for coordinated self-FEXT cancellation across multiple twisted-pairs. The proposed receiver treats the FEXT-impaired channel as a multiple-input multiple-output (MIMO) channel; it uses the sequential Monte Carlo (SMC) technique to exploit the sequential structure inherent in iterative cancellation techniques for MIMO decoding. On telephone loops with strong FEXT, the proposed algorithm shows 0.5-dB coding gain with respect to previously proposed techniques. Furthermore, being soft-input-soft-output in nature, the proposed SMC receiver can iteratively exchange extrinsic information with a MAP decoder to successively cancel FEXT, leading to a turbo FEXT canceller.

Telephone cable: overview and dielectric challenges

An overview of the common types of telephone wire and cable used in the United States and of related industry specifications is provided. Common insulating materials and selected electrical and physical parameters are discussed, along with several dielectric-related problems facing the industry. One is to reduce the migration of oil from cable filling gels into the insulation, where it adversely affects the electrical and physical properties. A second problem is how to reduce the overall fire hazard contributed by wire and cable installed in a building. A third problem is to develop twisted-pair copper cables that can handle increasingly higher data rates. >

Economic Analysis of Fiber Versus Alternative Media

The paper presents economic analysis of single-mode and multimode fiber optic cables in the telecommunications environment. Fiber optic cables are economically compared to alternative transmission media including twisted pair copper cables, screened copper cables, coaxial cables, and various radio facilities. Economic sensitivity to growth rates and digital office integration is performed to investigate variables influencing the economic study.