Two-band transmitter-receiver with dual radiation device
AssigneeSagem SA
InventorsMarc Recouly, Fernando Romao, Karim Ramsi
Life of this patent
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Abstract
To enable a use of a two-band type mobile telephone with a dual radiation circuit, a selector switch is placed between this dual radiation circuit and transmission channels in each of these bands. Given the emergence of the second harmonic resulting from the presence of the selector switch, the undesirable components are filtered with a filter. A part of the reactive components of this filter is between the radiating circuit and the selector switch, while the other part is in the channel to be filtered. Depending on the nature of the channel, the other part in the channel to be filtered has different values.
Claims19
A transmission circuit comprising a transmission channel for a carrier at a frequency f0, a transmission channel for a carrier at a frequency of f1 different from f0, a radiation circuit and a single selector switch to receive these two transmission channels and switch over one of these two transmission channels to the radiation circuit, wherein the transmission circuit comprises a single first filter element located between the selector switch and the radiation circuit, this first filter element being tuned to a second filter element located in the transmission channel at the frequency f0 to prevent the transmission, through this transmission channel at the frequency f0, of frequency components at the frequency f1, and the first filter element is tuned with a third filter element located in the transmission channel at the frequency f1 to enable the transmission, by this transmission channel at the frequency f1, of frequency components at the frequency f1.
A transmission/reception comprising:
- a first pair of reception channels respectively tuned to a frequency f0 and to a frequency f1, different from f0,
- a second pair of transmission channles respectively tuned to the frequency f0 and to the frequency f1,
- a first and a second radiation circuit,
- a first and a second diplexer,
- and a selector switch connected at input to the outputs of the two diplexers and at output to the two radiation circuits, to receive these two pairs of channels and switch over a transmission channel and a reception channel tuned to one and the same frequency on one of the radiation circuits, wherein:
- the first pair of reception channels is connected to two inputs of the first diplexer,
- the second pair of transmission channels are connected to two inputs of the second diplexer,
- the transmission/reception circuit comprises a single first filter element located between the selector switch and one of the radiation circuits, this first filter element being tuned with a second filter element located in the transmission channel at the frequency f0 to prevent the transmission by this transmission chamnel at the frequency f0, of frequency components at the frequency f1, and
- the first filter element is tuned with a third filter element located in the transmission channel at the frequency f1 to enable the transmission, by this transmission channel at the frequency f1, of frequency components at the frequency f1.
A transmission circuit comprising a transmission channel for a carrier at a frequency f0, a transmission channel for a carrier at a frequency of f1 different from f0, a radiation circuit and a selector switch to receive these two transmission channels and switch over one of these two transmission channels to the radiation circuit, wherein the transmission circuit comprises a first filter element located between the selector switch and the radiation circuit, this first filter element being tuned to a second filter element located in the transmission channel at the frequency f0 to prevent the transmission, through this transmission channel at the frequency f0, of frequency components at the frequency f1, wherein the first filter element is tuned with a third filter element located in the transmission channel at the frequency f1 to enable the transmission, by this transmission channel at the frequency f1, of frequency components at the frequency f1.
A transmission circuit comprising a transmission channel for a carrer at a frequency f0, a transmission channel for a carrier at a frequency of f1 different from f0, a radiation circuit and a selector switch to receive these two transmission channels and switch over one of these two transmission channels to the radiation circuit, wherein the transmission circuit comprises a first filter element located between the selector switch and the radiation circuit, this first filter element being tuned to a second filter element located in the transmission channel at the frequency f0 to prevent the transmission, through this transmission channel at the frequency f0, of frequency components at the frequency f1, and including, in cascade, a pair of node selector switches, an alternating selector switch and an antenna selector switch.
A transrnission/reception circuit comprising:
- a first pair of reception channels respectively tuned to a frequency f0 and to a frequency f1, different from f0,
- a second pair of transmission channels respectively tuned to the frequency f0 and to the frequency f1,
- a first and a second radiation circuit,
- a first and a second diplexer,
- in cascade, a pair of mode selector switches, an alternating selector switch and an antenna selector switch,
- and a selector switch connected at input to the outputs of the two diplexers and at output to the two radiation circuits, to receive these two pairs of channels and switch over a transmission channel and a reception channel tuned to one and the same frequency on one of the radiation circuits, wherein:
- the first pair of reception channels is connected to two inputs of the first diplexer, the second pair of transmission channels are connected to two inputs of the second diplexer, and
- the transmnission/reception circuit comprises a single first filter element located between the selector switch and one of the radiation circuits, this first filter element being tuned with a second filter element located in the transmission channel at the frequency f0 to prevent the transmission, by this transmission channel at the frequency f0, of frequency components at the frequency f1.
Dependencies are inferred from the claim text.