The PCM Data Sequence Controller described in this paper is used to interface a memory-controlled PCM encoder with a plated wire memory to form a unique digital data compression and storage system. The memory-controll...
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The PCM Data Sequence Controller described in this paper is used to interface a memory-controlled PCM encoder with a plated wire memory to form a unique digital data compression and storage system. The memory-controlled PCM encoder is used to select formats and convert input analog data channels into a PCM bit stream which is both transmitted and stored in a plated wire memory. The encoder is also used to retrieve information from the plated wire memory and retransmit it. The system provides both temporary and permanent data storage for the telemetering of data in a severe environment.
The development of PCM transmission system at the international and national levels is reviewed, including the basic and essential transmission parameters. The concept of the specific PCM transmission systems PCM 30/3...
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The development of PCM transmission system at the international and national levels is reviewed, including the basic and essential transmission parameters. The concept of the specific PCM transmission systems PCM 30/32 and PCM 30 is discussed, along with efforts towards the introduction of international standardization. The most important functions of the equipment, modules and plug-in units are described.
The stability of PCM communication networks is investigated. The research is in the general area of stability theory of time-lag systems which occur in communication sciences. The time-lag systems investigated occur i...
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The stability of PCM communication networks is investigated. The research is in the general area of stability theory of time-lag systems which occur in communication sciences. The time-lag systems investigated occur in pulse code modulation networks which are being introduced into telephone transmission systems as a means of increasing traffic carrying capacity. For synchronized operation of P. C. M. telephone exchanges, it is desired to ensure equality of oscillator frequency at every exchange. In order to keep the various oscillators synchronized, the frequency of each oscillator in the network is continually adjusted so as to reduce discrepancies revealed by incoming signals from adjacent telephone exchanges.
The PCM Data Sequence Controller described in this paper is used to interface a memory-controlled PCM encoder with a plated wire memory to form a unique digital data compression and storage system. The memory-controll...
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The PCM Data Sequence Controller described in this paper is used to interface a memory-controlled PCM encoder with a plated wire memory to form a unique digital data compression and storage system. The memory-controlled PCM encoder is used to select formats and convert input analog data channels into a PCM bit stream which is both transmitted and stored in a plated wire memory. The encoder is also used to retrieve information from the plated wire memory and retransmit it. The system provides both temporary and permanent data storage for the telemetering of data in a severe environment.
Three high-speed digital multiplexers utilizing pulse stuffing synchronization, are described. The first multiplexer converts twelve 8 Mbit/sec second-stage PCM signals into a 100 Mbit/sec pulse stream which can then ...
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Three high-speed digital multiplexers utilizing pulse stuffing synchronization, are described. The first multiplexer converts twelve 8 Mbit/sec second-stage PCM signals into a 100 Mbit/sec pulse stream which can then be transmitted over coaxial cables, low capacitance pair cables or into higher stage multiplexers. The second multiplexer combines four 100 Mbit/sec signals into a pair of 200 Mbit/sec signals. The third multiplexer combines eight 100 Mbit/sec signals into a pair of 400 Mbit/sec pulse streams. The outputs of the latter two multiplexers can be connected to high speed digital lines such as microwave radio links, millimetric wave guide systems, coaxial cable lines, etc.
The sync combination structures optimizing the sync channel parameters of a PCM system with various types of message distribution function and methods of sample coding are determined.
The sync combination structures optimizing the sync channel parameters of a PCM system with various types of message distribution function and methods of sample coding are determined.
The technique relies on synchronizing the measuring equipment with the signal in order to obtain amplitude samples at instants when the signal and noise are both present and when noise alone is present. It is shown th...
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The technique relies on synchronizing the measuring equipment with the signal in order to obtain amplitude samples at instants when the signal and noise are both present and when noise alone is present. It is shown that the mean and variance are sufficient for calculating signal-to-noise ratio (SNR). The signal power at the receiver input is derived from the SNR by utilizing the receiver characteristics. Additional noise introduced by the digitizer and band limiting introduced by the recorder are both accounted for.
The stability of PCM communication networks is investigated. The research is in the general area of stability theory of time-lag systems which occur in communication sciences. The time-lag systems investigated occur i...
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The stability of PCM communication networks is investigated. The research is in the general area of stability theory of time-lag systems which occur in communication sciences. The time-lag systems investigated occur in pulse code modulation networks which are being introduced into telephone transmission systems as a means of increasing traffic carrying capacity. For synchronized operation of P. C. M. telephone exchanges, it is desired to ensure equality of oscillator frequency at every exchange. In order to keep the various oscillators synchronized, the frequency of each oscillator in the network is continually adjusted so as to reduce discrepancies revealed by incoming signals from adjacent telephone exchanges.
In a previous paper, the basic introductory information on pulse code modulation (PCM) switching was published. The article presented the T1 digital carrier system, principles of synchronization, and the advantages of...
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In a previous paper, the basic introductory information on pulse code modulation (PCM) switching was published. The article presented the T1 digital carrier system, principles of synchronization, and the advantages of supermultiplexing along with other pertinent information. This article deals primarily with the selection and detailed operation of the PCM switching network. It describes a practical configuration suitable to the needs of the general system and is consistent with present day technology.
Employing the "statistical thermodynamic formalism" developed in an earlier paper, it is possible to determine "compact" sets of transmission times for the words of PCM (pulse code modulation) mess...
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