(19)
(11) EP 0 291 676 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
29.03.1989 Bulletin 1989/13

(43) Date of publication A2:
23.11.1988 Bulletin 1988/47

(21) Application number: 88105345.8

(22) Date of filing: 02.04.1988
(51) International Patent Classification (IPC)4G08G 1/09
(84) Designated Contracting States:
DE FR GB

(30) Priority: 21.05.1987 IT 2060887

(71) Applicant: RAI RADIOTELEVISIONE ITALIANA
I-10135 Torino (IT)

(72) Inventor:
  • Angeli, Franco
    I-10137 Turin (IT)

(74) Representative: Forattini, Amelia et al
c/o Internazionale Brevetti Ingg. ZINI, MARANESI & C. S.r.l. Piazza Castello 1
20121 Milano
20121 Milano (IT)


(56) References cited: : 
   
       


    (54) Apparatus for the isofrequential broadcasting of radio programmes, particularly in frequency modulation, along a highway


    (57) The apparatus is aimed at radio receivers on board vehicles in movement along a highway without changes in tuning, and comprises: a plurality of emitting antennae (12, 14) arranged at intervals along said highway, and respective radio-frequency amplifiers (36, 42) connected to feed said antennae; an optical fiber line (18) adjacent to said highway, fed at one end by an optical transmitter (28) driven by a radio-frequency signal to be broadcast; means (30, 38) for tapping the radio-frequency signal from the optical fiber line at each radio-frequency amplifier; and delay means (34, 40) for delaying the radio-frequency signal having their input connected to the output of said tapping means and their output connected to said radio-frequency amplifiers; the delay introduced by each of said delay means being such that in the equisignal region between every two adjacent emitting antennae the broadcast signal is substantially coherent.







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