DOI:10.1049/ree.1980.0047

出版商:IERE    

年代:1980

数据来源: IET

DOI:10.1049/ree.1980.0049

出版商:IERE    

年代:1980

数据来源: IET

DOI:10.1049/ree.1980.0050

出版商:IERE    

年代:1980

数据来源: IET

摘要:

The paper describes a system for detecting and attenuating impulsive noise on gramophone records. Fast transitions and short duration are shown to be the essential characteristics of the impulsive noise waveform and a detector which uses these characteristics to distinguish between the noise and the recorded signal is described. Several methods of producing a noise-free approximation to the recorded signal are discussed and compared. A simple attenuation technique is shown to be as subjectively acceptable as more complex techniques. The designs of delay line and attenuator for optimum performance are considered and the subjective performance of the system is assessed.

DOI:10.1049/ree.1980.0051

出版商:IERE    

年代:1980

数据来源: IET

摘要:

This paper establishes the feasibility of transmitting high integrity data, via a leaky coaxial feeder, at much higher rates than are normally considered possible over a mobile radio channel. Both signal variations and error rates are examined. The use of diversity techniques to improve performance are considered and possible system layouts are presented.

DOI:10.1049/ree.1980.0052

出版商:IERE    

年代:1980

数据来源: IET

摘要:

A large area coverage radio system with telephone access is described. Two operator-controlled systems have been installed on British Rail. This paper describes the development of a stored program automatic radio connection system, which allows direct dialling between individual mobile radio users and access to the British Rail automatic trunk telephone network. Emergency override access from the mobile radios is provided.

DOI:10.1049/ree.1980.0053

出版商:IERE    

年代:1980

数据来源: IET

摘要:

Pulse code modulation systems as used in telephony networks are briefly described with particular regard to the inherent quantizing distortion (q.d.). Test methods for the evaluation of signal to q.d. ratio, from analogue input to analogue output, are reviewed. Three test stimuli are considered and their advantages and disadvantages discussed. The three stimuli are a sinusoid, a band-limited noise signal and a band-limited pseudo-random noise signal.

DOI:10.1049/ree.1980.0054

出版商:IERE    

年代:1980

数据来源: IET

摘要:

Many algorithms have been suggested1−5in the past to design combinational logic circuits using multiplexers. An alternative method, based on the Boolean matrix approach, is suggested here. The method is simpler and faster compared to existing methods and can be easily programmed on a computer. Finally, the proper selection of multiplexers is suggested by applying simple empirical rules.

DOI:10.1049/ree.1980.0055

出版商:IERE    

年代:1980

数据来源: IET

摘要:

A holographic recording system, based on the use of lowpower laser sources and high-resolution photographic film, is briefly outlined. It was devised principally for the archival storage of high-quality digital television signals and these requirements are reviewed. The development of suitable electro-optic transducers is difficult, largely because of the high data-transfer rates involved, but some progress has been made. Experimental versions of the transducers have been assembled to form a recording apparatus for writing and reading investigations at realtime rates. The results of some initial experiments are given which illustrate various problems that have been encountered, particularly with regard to the recording medium.

DOI:10.1049/ree.1980.0056

出版商:IERE    

年代:1980

数据来源: IET