DOI:10.1049/ree.1982.0001

出版商:IERE    

年代:1982

数据来源: IET

DOI:10.1049/ree.1982.0002

出版商:IERE    

年代:1982

数据来源: IET

摘要:

The need to visualize thermal radiation is outlined. The characteristics of radiant energy and the transmission properties of the atmosphere are discussed to define the spectral range of interest. Practical methods of detecting thermal radiation are reviewed and the benefit of cooling the detector highlighted. Techniques whereby the detector can be made to interrogate the scene are described and contrasted. The manner by which the detected signal is processed is described with reference to several new electronic components. Finally some examples of present day systems are presented with examples of typical thermal imagery.

DOI:10.1049/ree.1982.0003

出版商:IERE    

年代:1982

数据来源: IET

摘要:

The characteristics required for a studio format digital recorder are considered and variable-speed operation for the Type B and C systems is described. The implication of the picture-in-shuttle techniques are considered and also the reasons for adopting a helical rather than transverse format. Coding systems are then compared in some detail with special reference to error detection and correction and it is concluded that the Miller Squared code is superior to the 8/10 code. Brief comment is made on the adoption of a broadcast digital standard.

DOI:10.1049/ree.1982.0004

出版商:IERE    

年代:1982

数据来源: IET

摘要:

An important parameter in the design of mobile radio systems is the co-channel protection ratio. New measurements, based on realistic subjective testing procedures using speech modulation, are presented for the a.m. case. The critical importance of audible carrier interactions is demonstrated.Mean values of protection ratio which were graded by users as ‘perceptible but not disturbing’ decreased from greater than 30 dB to approximately 15 dB when the carrier frequency offset was reduced from 1 kHz to 100 Hz.Extreme variability between subjects makes reliable experimental evaluation of protection ratio an expensive and time-consuming procedure.

DOI:10.1049/ree.1982.0005

出版商:IERE    

年代:1982

数据来源: IET

摘要:

This paper describes a microprocessor controller for limited-function, special-purpose robots. Both hardware and software for the controller were developed in modular form so that appropriate modules can be selected to suit a particular robot configuration. Two levels of sequence programming, defining the task to be performed by a robot, can be utilized. Low-level sequence programming can be used by a trained operator but is time consuming and error prone. High-level sequence programming can be achieved using a software communications module which prompts the operator so that negligible training is required and sequences can be developed efficiently.

DOI:10.1049/ree.1982.0006

出版商:IERE    

年代:1982

数据来源: IET

摘要:

Different approaches for the integration of mm-wave components have been presented recently, suggesting image line or shielded microstrip line for example. A very promising attempt employs quasi-planar structures, like fin-line, and related line configurations for this purpose. The paper gives a survey of various components being developed in the frequency range from 18 to 170 GHz using this approach.Broadband p-i-n-attenuators achieve an insertion loss below 1 dB and an isolation better than 25 dB covering either one or two entire waveguide bands. Narrowband resonator-type attenuators need only one diode to achieve similar results. At 94 GHz the attenuation of such a device can be adjusted between 1.5 and 35 dB. Fin-line detectors have been built between 18 and 170 GHz, with minimum sensitivity ranges from 400 to 100 mV/mW, depending on frequency. The conversion loss of a planar balanced mixer developed for Ka-band (26.5–40 GHz) amounts to 5 dB in a narrowband version and to 6–8 dB in a broadband, octave-wide version (18–40 GHz). For 60 GHz, a conversion loss down to 6.5 dB has been achieved. The unique advantage of the fin-line technique is demonstrated by a completely integrated Ka-band receiver front end, containing p-i-n-s.t.c, mixer and local oscillator. Fin-line couplers necessary for other integrated circuits have shown coupling factors up to crossover operation with full waveguide bandwidth.

DOI:10.1049/ree.1982.0007

出版商:IERE    

年代:1982

数据来源: IET