EP0355973A2
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Digital mobile phone
Assignee: Nokia Oyj
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Filing: 1989-07-13
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Granted: —
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Expires: 2009-07-13
Abstract
Abstract In a digital mobile phone based on time-division multiplexing (TDMA) a separate RF antenna switch is replaced by a duplex filter of the type used in analog technique.
Inventors
- 👤 Erkki Juhani Kuisma
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 15:05
CPC Classifications
H; H04; H04B; H04B1/00; H04B1/38; H04B1/40; H04B1/50; H04B1/52; H04B1/525; H04B1/44; H04B1/48
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
49 words
An antenna switch circuit for a digital mobile phone based on time-division mutiplexing (TDMA), characterized in that a filter of duplex type is used as an antenna switch of the mobile phone in order to couple the antenna to the mobile phone receiver input and to its transmitter output.
Claim 2
Dependent Claim
49 words
An antenna switch circuit for a digital mobile phone based on time-division mutiplexing (TDMA), characterized in that a filter of duplex type is used as an antenna switch of the mobile phone in order to couple the antenna to the mobile phone receiver input and to its transmitter output.
Claim 3
Dependent Claim
77 words
An antenna switch circuit according to claim 1, characterized in that the antenna is coupled to the filter so that in the reception band the transmission filter (S2′) presents a very high impedance to the antenna and the reception filter (S1′) presents an impedance equal to that of the antenna and in the transmission band the reception filter (S1′) exhibits a very high impedance to the antenna and the transmission filter (S2′) is diposed on the antenna.
Claim 4
Dependent Claim
17 words
An antenna switch circuit according to claim 1, characterized in that the filter is a ceramic filter.
Claim 5
Dependent Claim
18 words
An antenna switch circuit according to claim 1, characterized in that the filter is a strip line filter.
Claim 6
Dependent Claim
18 words
An antenna switch circuit according to claim 1, characterized in that the filter is based on helical resonators.
Claim 7
Dependent Claim
17 words
An antenna switch circuit according to claim 1, characterized in that the filter is a SAW filter.
References Cited (Backward Citations)
No citation records indexed.
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