. "568979" . . . "2/3" . . . . "La\u0161tovi\u010Dka, Jan" . "47" . "Telecommunications via ionospheric reflection of radio signals of ground-based transmitters are a traditional area. However, this technique is still in use in telecommunications, broadcasting, etc. Various problems have not yet been solved and some of them were studied in Working group 3 (WG 3). Structure of WG 3 and the terms of reference of its four working packages are described in the introductory paper by Zolesi and Cander (2004). Here we describe the main results achieved in COST 271 in the following areas: i) large-scale fluctuations of planetary and gravity waves; ii) development od a new type of HF channel simulator; iii) geomagnetic storm effects on the F1-region ionosphere; iv) the sporadic E-layer and spread-F phenomena; v) the HF radio wave propagation over northerly path; vi) how to increase the bit rate in ionospheric radio links. In general, substantial progress was achieved but some problems remain open for future investigations"@en . "[811CDB9ADE8E]" . "9"^^ . . "IT - Italsk\u00E1 republika" . . "Bourdillon, A." . . "ionospheric reflection; telecommunications; gravity waves; planetary waves"@en . "Ionospheric effects on terrestrial communications: Working Group 3 overview"@en . "1269;1277" . "P(IBS3012007), P(OC 271.10), Z(AV0Z3042911)" . "2"^^ . "Ionospheric effects on terrestrial communications: Working Group 3 overview" . . . "Telecommunications via ionospheric reflection of radio signals of ground-based transmitters are a traditional area. However, this technique is still in use in telecommunications, broadcasting, etc. Various problems have not yet been solved and some of them were studied in Working group 3 (WG 3). Structure of WG 3 and the terms of reference of its four working packages are described in the introductory paper by Zolesi and Cander (2004). Here we describe the main results achieved in COST 271 in the following areas: i) large-scale fluctuations of planetary and gravity waves; ii) development od a new type of HF channel simulator; iii) geomagnetic storm effects on the F1-region ionosphere; iv) the sporadic E-layer and spread-F phenomena; v) the HF radio wave propagation over northerly path; vi) how to increase the bit rate in ionospheric radio links. In general, substantial progress was achieved but some problems remain open for future investigations" . . . "1"^^ . "Telekomunikace odrazem radiov\u00FDch sign\u00E1l\u016F pozemn\u00EDch vys\u00EDla\u010D\u016F od ionosf\u00E9ry je tradi\u010Dn\u00ED oblast\u00ED. Av\u0161ak tato technika se st\u00E1le pou\u017E\u00EDv\u00E1 v telekomunikac\u00EDch, r\u00E1diov\u00E9m vys\u00EDl\u00E1n\u00ED atd. \u0158ada probl\u00E9m\u016F je\u0161t\u011B nebyla vy\u0159e\u0161ena. N\u011Bkter\u00E9 z nich byly studov\u00E1ny pracovn\u00ED skupinou 3 (WG-3). Struktura WG-3 a \u00FAkoly jej\u00EDch \u010Dty\u0159 pracovn\u00EDch t\u00FDm\u016F jsou popos\u00E1ny v \u00FAvodn\u00EDm \u010Dl\u00E1nku Zolesi a Cander (2004). Zde popisujeme hlavn\u00ED v\u00FDsledky dosa\u017Een\u00E9 v COST271 v n\u00E1sleduj\u00EDc\u00EDch oblastech: i) velkorozm\u011Brov\u00E9 fluktuace planet\u00E1rn\u00EDch a gravita\u010Dn\u00EDch vln; ii) v\u00FDvoj nov\u00E9ho typu simul\u00E1toru VF kan\u00E1lu; iii) vliv geomagnetick\u00FDch bou\u0159\u00ED na F1-vrstvu ionosf\u00E9ry; iv) sporadick\u00E1 vrstva E a jev spread-F; v) \u0161\u00ED\u0159en\u00ED VF radiov\u00FDch vln na severn\u00EDch tras\u00E1ch; vi) jak zv\u00FD\u0161it rychlost p\u0159enosu ionosf\u00E9rick\u00FDch radiov\u00FDch kan\u00E1l\u016F. Celkov\u011B byl dosa\u017Een zna\u010Dn\u00FD pokrok, ale n\u011Bkter\u00E9 probl\u00E9my z\u016Fst\u00E1vaj\u00ED otev\u0159en\u00E9 pro dal\u0161\u00ED v\u00FDzkum"@cs . "Ionospheric effects on terrestrial communications: Working Group 3 overview" . "Vliv ionosf\u00E9ry na pozemn\u00ED komunikace: p\u0159ehled v\u00FDsledk\u016F pracovn\u00ED skupiny 3"@cs . . . . "1593-5213" . "RIV/68378289:_____/04:00104044!RIV/2005/AV0/A04005/N" . "Vliv ionosf\u00E9ry na pozemn\u00ED komunikace: p\u0159ehled v\u00FDsledk\u016F pracovn\u00ED skupiny 3"@cs . . "Ionospheric effects on terrestrial communications: Working Group 3 overview"@en . . "Annals of Geophysics" . . "RIV/68378289:_____/04:00104044" .