| (19) |
 |
|
(11) |
EP 0 178 795 A3 |
| (12) |
EUROPEAN PATENT APPLICATION |
| (88) |
Date of publication A3: |
|
30.09.1987 Bulletin 1987/40 |
| (43) |
Date of publication A2: |
|
23.04.1986 Bulletin 1986/17 |
| (22) |
Date of filing: 18.09.1985 |
|
|
| (84) |
Designated Contracting States: |
|
AT BE CH DE FR IT LI LU NL SE |
| (30) |
Priority: |
09.10.1984 GB 8425525
|
| (71) |
Applicant: STANDARD TELEPHONES AND CABLES PUBLIC LIMITED COMPANY |
|
() |
|
| (72) |
Inventors: |
|
- Lewin, Leonard
()
- Norris, Andrew Peter
()
|
|
| |
|
(57) A buoyant antenna comprises a slot (10) formed by the edge opening in a single turn
roll-resonator of metal clad plastic dielectric sheet material (11), the slot being
substantially one free-space wavelength long at the operating frequency and short
circuited at each end (12). Varactor diodes (13) are connected across the slot. Low
frequency modulation of the varactor diode bias effects tuning of the antenna. The
roll-resonator is encased in a jacket of foam dielectric (20). A pilot signal can
be injected, via the varactor feed lines.