Showing papers on "Co-channel interference published in 1986"

Main Effect of Mutual Interference in Radio Communication Systems Using Broad-Band Transmitters

Abstract: Present-day radio communication systems employing antijam techniques, such as frequency hopping or spread spectrum, require that the transmitter final stage be a broad-band solid-state device. An analysis of such radio communication systems has shown that these systems suffer from the effects of intermodulation (IM) products generated within the transmitters, especially under collocation situations. A qualitative analysis of the transmitter IM-product interference sources is followed by the development of a computational method for obtaining their disturbing effects on a VHF/FM radio system operating under severe tactical collocation scenarios. The computed results for other mutual interference sources upon the system are also presented. The numerical results of the developed computer printout are discussed and conclusions presented, which contribute to obtaining a clearer insight into the mutual-interference sources within the system, especially from the transmitter IM disturbances.

Method of synchronizing radio transmitters for synchronous radio transmission

Abstract: In transmission by radio of personal paging calls synchronous radio transmission from several transmitters is often used, i.e. the transmitters send on the same frequency. The characters of the call must also be sent simultaneously from the transmitters so that they shall be correctly comprehended by the receivers. A method and an apparatus are described here for synchronizing the separate transmitters (2:2, 3:16) such as to transmit on the same frequency.

Broad Signal Constraints for Management of the Spectrum in Telephone Loop Cables

Abstract: It is shown that the maximum instantaneous near-end crosstalk interference voltage on a cable pair can be constrained by restricting the energy transmitted in any time interval of a duration determined by the cable properties. The maximum interference is proportional to the sum of the energies in the impulse responses of the equalized near-end crosstalk paths to the disturbed pair.

Predicting CNR Frequency Hopping Interference by Simulation

Abstract: A computer model has been developed to enable studies of frequency hopping interference The program is capable of accurately simulating the interference imposed on a frequency hopping or fixed frequency receiver when it is subjected to a multitude of interference sources, such as communication transmitters, jammers and ambient noise The model handles extreme cosite situations as well as distant emitters Results are presented as the cumulative distribution for the RF signal-to-interference ratio The computed interference can also be imposed on a real RF link between a transmitter and the receiver being interfered This is done under controlled laboratory conditions and enables realistic demonstrations of interference effects and measurements of performance parameters such as synchronization probability, bit error rate and speech intelligibility

Co-Channel Interference in a Cellular Rural Radio Telephone System.

Abstract: i Preface Issue 7 of SRSP-503 is hereby released to allow better coverage and higher throughput for mobile data services in rural and remote areas. Changes include: • increase of the EIRP limits outside of urban areas • increase of the EIRP limit for mobile terminals • update of the coordination distance for base stations using the increased EIRP limits • additional updates and editorial corrections This Standard Radio System Plan (SRSP) replaces SRSP-503, Issue 6.

Interference issues affecting Ku-band small-aperture satellite systems

Abstract: 1. Abstract Thousands of small aperture Ku band Earth Stations are being deployed nationally in private satellite networks. Concurrently, orbital separation of communication satellites is shrinking t o 2'. Therefore adjacent satellite system interference effects are increasingly important. This paper models typical TDMA, SCPC and Video Systems, and evaluates interference effects caused by and into small aperture systems. while worst-case conditions may affect some applications, the analysis shows that small aperture Ku band networks coexist peacefully with other services.