Manitoba Telecom Services

About: Manitoba Telecom Services is a based out in . It is known for research contribution in the topics: Telephone line & Signal. The organization has 15 authors who have published 15 publications receiving 379 citations.

Distributed network synchronization system

Abstract: A synchronization system is provided for a tree-type transmission system comprising a central station connected to a plurality of remote stations in an effectively sequential manner, each station including transmitting and receiving means for digital data in a sequence of frames. Each remote station is instructed regularly by the central station of the time delay between the remote station and the central station. The remote station stores the time delay and arranges to advance information transmitted by the remote station so as to be received by the central station within the proper position in the frame. The time delay is measured by the central station by sensing a pattern of bits repetitively transmitted by the remote station and comparing the received pattern with a stored pattern and counting the number of shifts of the received pattern necessary to match the stored pattern. The delay stored by the remote station is tuned to one quarter of a bit to ensure accurate synchronization.

Video distribution control system

Abstract: A subscriber distribution terminal is connected to the transmission medium for serving a group of subscribers Within the distribution control terminal is located a plurality of television converters A local oscillator in each of the converters is controlled by a microprocessor, which establishes the channel selected from the multi-channel television signal received from the transmission medium The output of each converter is connected to a subscriber drop which is connected to the subscribers television set

Video and data distribution module with subscriber terminal

Abstract: A subscriber data distribution system comprising first means for translating data received from a transmission line and transmitting the data to a subscriber terminal via a subscriber drop, second means for translating data received from a subscriber terminal and transmitting the data to the transmission line, the first and second means including means for isolating the transmission line from the subscriber terminal, and for regenerating the data transmitted both to and from the subscriber terminal.

Key management system for open communication environments

Abstract: A telecommunications security device for use on the communication medium includes a first and a second security unit each arranged to be inserted into for example the telephone line adjacent a user device. The units are identical and therefore either can act as a central unit for example for a computer access port with the other providing one of a set of remote units. Each unit includes a separable memory module with all the modules having a memory storing identical information. The information stored includes a plurality of pairs of random signals one of each pair providing a request signal and the other the security code. The central unit on receipt of a telephone call provides a signal requesting an ID code from the remote unit and on receipt of the ID code issues from one of the pairs the security code request signal. On matching the received code with the expected code a transmission gate is opened. The pairs are used in turn until all of the pairs have been used whereupon an indicator shows this condition. The modules can be removed and the memory re-written with fresh pairs of codes. The key includes a security logic circuit which controls access to the numbers to a fixed set of access rules allowing authentication and/or encryption and providing security against unauthorized access.

Management Selection by Multiple-Domain Assessment: I. Concurrent Validity:

Abstract: A large-scale concurrent validity study is described in which 321 first-level management employees in a Canadian provincial telephone company were given a comprehensive assessment battery and were rated on their work performance. Measures from five assessment domains-cognitive abilities, personality/motivational traits, administrative skills, biodata, and supervisory judgment were administered in one-day assessment sessions. Independent assessments of 12 work-performance appraisal dimensions were provided by 165 higher-level supervisors of the 321 participants, using a combination of behaviorally anchored rating scales and behavioral observation scales. The assessment domains were examined individually as to their predictive efficacy, and simple composites of measures from several domains were correlated with the criterion appraisal dimension scores. Concurrent validity coefficients obtained for all 12 criterion dimensions and for an overall management performance criterion ranged from .36 to .56 for wome...