| 摘要 |
radio electronic equipment. SUBSTANCE: device may be used for filters of IF and carrier frequency in cordless telephones, pagers, mobile communication equipment, etc. Application of electric signal to unidirectional converter, which has elementary circuits of opposite-phase excitation electrodes and reflecting electrode, results in excitation of surface acoustic waves, which travel in direct and reverse directions. Natural directivity of emission is ensured by design of substrate, which is made from monocrystal, in which mechanical and electromagnetic constituents of propagating surface acoustic wave are shifted within range of 0°< DELTAϕ< ±90°. Width of first, second and third excitation electrode in each elementary conforms to conditions lambda/7 < b1< 2/3, lambda/7 < b3< lambda/4, lambda/7 < b5< lambda/4, where lambda is wavelength at mean frequency. Distance between first, second and third excitation electrodes conforms to conditions lambda/7 < b2< 2/4, lambda/7 < b4< 2/4. Width of reflecting electrode is within range of lambda/7 < b1< 2/3, lambda/7 < b1< 2/3. Distance between third excitation electrode and reflecting electrode is within range of lambda/7 < b6< 2/4. Reflecting electrode is connected to potential or ground adding bus. Polarity of connection of reflecting electrode to said buses is opposite to polarity of connection of third excitation electrode to same buses. Adjacent elementary circuits are arranged with period of L = (2n+1).lambda/2, n=1, 2, 3, .: Polarity of connection of adjacent elementary circuits to potential and ground adding buses is alternating. EFFECT: decreased insertion losses. 4 dwg
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