Portable radio apparatus
First Claim
Patent Images
1. A portable radio apparatus, comprising:
- an antenna for transmitting and receiving a radio signal;
a radio circuit for decoding the radio signal received via the antenna and encoding a signal to be transmitted as a radio signal via the antenna; and
a matching circuit for providing an impedance match between the antenna and the radio circuit;
wherein;
the matching circuit includes at least one inductive elements connected in parallel to the antenna; and
at least one of the inductive elements has a Q factor more than a predetermined value, the Q factor being expressed as follows;
Q=ω
L/R wherein R indicates a resistance component, L is an inductance component, and ω
designates an angular frequency of the radio signal.
2 Assignments
0 Petitions
Accused Products
Abstract
A portable radio apparatus capable of providing an impedance match with an antenna and a simple matching circuit for all frequency components of a frequency band to be used. A portable radio apparatus includes a whip antenna, a matching circuit, a radio section changing switch, a first frequency band receiver, and a first frequency band transmitter. A parallel inductor causing a resonance with a frequency lower than a resonance frequency of the antenna is connected in parallel to the antenna for a two-resonance characteristic to thereby conduct a wide-band operation.
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Citations
50 Claims
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1. A portable radio apparatus, comprising:
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an antenna for transmitting and receiving a radio signal;
a radio circuit for decoding the radio signal received via the antenna and encoding a signal to be transmitted as a radio signal via the antenna; and
a matching circuit for providing an impedance match between the antenna and the radio circuit;
wherein;
the matching circuit includes at least one inductive elements connected in parallel to the antenna; and
at least one of the inductive elements has a Q factor more than a predetermined value, the Q factor being expressed as follows;
Q=ω
L/Rwherein R indicates a resistance component, L is an inductance component, and ω
designates an angular frequency of the radio signal. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 10, 11, 12, 13, 14, 15, 16, 17, 18, 20, 21, 22, 23, 24, 25, 26, 27, 28, 30, 31, 32, 33, 34, 35, 36, 37, 38, 40, 41, 42, 43, 44, 45, 46, 47, 48, 50)
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2. A portable radio apparatus in accordance with claim 1, wherein:
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the matching circuit is a π
type circuit in which a first inductive element is connected in parallel on the side of the antenna and a second inductive element is connected in parallel on the side of the radio circuit; and
the first inductive element has a Q factor more than a Q factor of the second inductive element.
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3. A portable radio apparatus in accordance with claim 1, wherein:
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the matching circuit is a π
type circuit in which a first inductive element is connected in parallel on the side of the antenna and a second inductive element is connected in parallel on the side of the radio circuit;
the first inductive element has a Q factor more than a Q factor of the second inductive element; and
the Q factor of the first inductive element takes a value, which sets radiation efficiency of the antenna to a value equal to or more than a predetermined value when the radio signal is transmitted.
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4. A portable radio apparatus in accordance with claim 1, wherein:
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the matching circuit is a π
type circuit in which a first inductive element is connected in parallel on the side of the antenna and a second inductive element is connected in parallel on the side of the radio circuit;
the first inductive element has a Q factor more than a Q factor of the second inductive element; and
the Q factor of each of the first and second inductive elements takes a value, which sets radiation efficiency of the antenna to a value equal to or more than a predetermined value when the radio signal is transmitted.
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5. A portable radio apparatus in accordance with claim 1, wherein the Q factor of each of the inductive elements is more than 40.
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6. A portable radio apparatus in accordance with claim 1, wherein:
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the matching circuit is a π
type circuit in which a first inductive element is connected in parallel on the side of the antenna and a second inductive element is connected in parallel on the side of the radio circuit;
the first inductive element has a Q factor more than a Q factor of the second inductive element; and
the Q factor of each of the inductive elements is more than 40.
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7. A portable radio apparatus in accordance with claim 1, wherein:
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the matching circuit is a π
type circuit in which a first inductive element is connected in parallel on the side of the antenna and a second inductive element is connected in parallel on the side of the radio circuit;
the first inductive element has a Q factor more than a Q factor of the second inductive element;
the Q factor of the first inductive element takes a value, which sets radiation efficiency of the antenna to a value equal to or more than a predetermined value when the radio signal is transmitted; and
the Q factor of each of the inductive elements is more than 40.
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8. A portable radio apparatus in accordance with claim 1, wherein:
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the matching circuit is a π
type circuit in which a first inductive element is connected in parallel on the side of the antenna and a second inductive element is connected in parallel on the side of the radio circuit;
the first inductive element has a Q factor more than a Q factor of the second inductive element;
the Q factor of each of the first and second inductive elements takes a value, which sets radiation efficiency of the antenna to a value equal to or more than a predetermined value when the radio signal is transmitted; and
the Q factor of each of the inductive elements is more than 40.
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10. A portable radio apparatus in accordance with claim 6, wherein the matching circuit is a π
- type circuit in which a first capacitive element is connected in parallel on the side of the antenna and a second capacitive element is connected in parallel on the side of the radio circuit.
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11. A portable radio apparatus in accordance with claim 1, wherein:
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the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands; and
the antenna has different two resonance frequencies in one of the frequency bands.
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12. A portable radio apparatus in accordance with claim 2, wherein:
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the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands; and
the antenna has different two resonance frequencies in one of the frequency bands.
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13. A portable radio apparatus in accordance with claim 3, wherein:
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the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands; and
the antenna has different two resonance frequencies in one of the frequency bands.
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14. A portable radio apparatus in accordance with claim 4, wherein:
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the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands; and
the antenna has different two resonance frequencies in one of the frequency bands.
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15. A portable radio apparatus in accordance with claim 5, wherein:
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the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands; and
the antenna has different two resonance frequencies in one of the frequency bands.
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16. A portable radio apparatus in accordance with claim 6, wherein:
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the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands; and
the antenna has different two resonance frequencies in one of the frequency bands.
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17. A portable radio apparatus in accordance with claim 7, wherein:
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the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands; and
the antenna has different two resonance frequencies in one of the frequency bands.
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18. A portable radio apparatus in accordance with claim 8, wherein:
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the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands; and
the antenna has different two resonance frequencies in one of the frequency bands.
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20. A portable radio apparatus in accordance with claim 10, wherein:
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the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands; and
the antenna has different two resonance frequencies in one of the frequency bands.
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21. A portable radio apparatus in accordance with claim 1, wherein:
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the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands; and
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic.
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22. A portable radio apparatus in accordance with claim 2, wherein:
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the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands; and
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic.
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23. A portable radio apparatus in accordance with claim 3, wherein:
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the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands; and
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic.
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24. A portable radio apparatus in accordance with claim 4, wherein:
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the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands; and
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic.
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25. A portable radio apparatus in accordance with claim 5, wherein:
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the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands; and
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic.
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26. A portable radio apparatus in accordance with claim 6, wherein:
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the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands; and
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic.
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27. A portable radio apparatus in accordance with claim 7, wherein:
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the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands; and
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic.
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28. A portable radio apparatus in accordance with claim 8, wherein:
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the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands; and
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic.
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30. A portable radio apparatus in accordance with claim 10, wherein:
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the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands; and
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic.
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31. A portable radio apparatus in accordance with claim 1, further comprising:
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a detector for detecting whether the antenna is in an expanded state in which the antenna is expanded; and
an expansion matching circuit impedance of which matches with the antenna in the expanded state in a particular frequency band when the expansion matching circuit is connected to the matching circuit;
wherein;
the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands;
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic; and
the expansion matching circuit is connected to the matching circuit when the antenna is in the expanded state and a particular one of the frequency bands is selected.
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32. A portable radio apparatus in accordance with claim 2, further comprising:
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a detector for detecting whether the antenna is in an expanded state in which the antenna is expanded; and
an expansion matching circuit impedance of which matches with the antenna in the expanded state in a particular frequency band when the expansion matching circuit is connected to the matching circuit;
wherein;
the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands;
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic; and
the expansion matching circuit is connected to the matching circuit when the antenna is in the expanded state and a particular one of the frequency bands is selected.
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33. A portable radio apparatus in accordance with claim 3, further comprising:
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a detector for detecting whether the antenna is in an expanded state in which the antenna is expanded; and
an expansion matching circuit impedance of which matches with the antenna in the expanded state in a particular frequency band when the expansion matching circuit is connected to the matching circuit;
wherein;
the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands;
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic; and
the expansion matching circuit is connected to the matching circuit when the antenna is in the expanded state and a particular one of the frequency bands is selected.
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34. A portable radio apparatus in accordance with claim 4, further comprising:
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a detector for detecting whether the antenna is in an expanded state in which the antenna is expanded; and
an expansion matching circuit impedance of which matches with the antenna in the expanded state in a particular frequency band when the expansion matching circuit is connected to the matching circuit;
wherein;
the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands;
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic; and
the expansion matching circuit is connected to the matching circuit when the antenna is in the expanded state and a particular one of the frequency bands is selected.
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35. A portable radio apparatus in accordance with claim 5, further comprising:
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a detector for detecting whether the antenna is in an expanded state in which the antenna is expanded; and
an expansion matching circuit impedance of which matches with the antenna in the expanded state in a particular frequency band when the expansion matching circuit is connected to the matching circuit;
wherein;
the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands;
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic; and
the expansion matching circuit is connected to the matching circuit when the antenna is in the expanded state and a particular one of the frequency bands is selected.
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36. A portable radio apparatus in accordance with claim 6, further comprising:
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a detector for detecting whether the antenna is in an expanded state in which the antenna is expanded; and
an expansion matching circuit impedance of which matches with the antenna in the expanded state in a particular frequency band when the expansion matching circuit is connected to the matching circuit;
wherein;
the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands;
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic; and
the expansion matching circuit is connected to the matching circuit when the antenna is in the expanded state and a particular one of the frequency bands is selected.
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37. A portable radio apparatus in accordance with claim 7, further comprising:
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a detector for detecting whether the antenna is in an expanded state in which the antenna is expanded; and
an expansion matching circuit impedance of which matches with the antenna in the expanded state in a particular frequency band when the expansion matching circuit is connected to the matching circuit;
wherein;
the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands;
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic; and
the expansion matching circuit is connected to the matching circuit when the antenna is in the expanded state and a particular one of the frequency bands is selected.
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38. A portable radio apparatus in accordance with claim 8, further comprising:
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a detector for detecting whether the antenna is in an expanded state in which the antenna is expanded; and
an expansion matching circuit impedance of which matches with the antenna in the expanded state in a particular frequency band when the expansion matching circuit is connected to the matching circuit;
wherein;
the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands;
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic; and
the expansion matching circuit is connected to the matching circuit when the antenna is in the expanded state and a particular one of the frequency bands is selected.
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40. A portable radio apparatus in accordance with claim 10, further comprising:
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a detector for detecting whether the antenna is in an expanded state in which the antenna is expanded; and
an expansion matching circuit impedance of which matches with the antenna in the expanded state in a particular frequency band when the expansion matching circuit is connected to the matching circuit;
wherein;
the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands;
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic; and
the expansion matching circuit is connected to the matching circuit when the antenna is in the expanded state and a particular one of the frequency bands is selected.
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41. A portable radio apparatus in accordance with claim 1, further comprising:
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a detector for detecting whether the antenna is in an expanded state in which the antenna is expanded; and
an expansion matching circuit impedance of which matches with the antenna in the expanded state in a particular frequency band when the expansion matching circuit is connected to the matching circuit;
wherein;
the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands;
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic;
the expansion matching circuit is connected to the matching circuit when the antenna is in the expanded state and a particular one of the frequency bands is selected; and
impedance of the antenna in the expanded state matches that of the matching circuit in a frequency band for which the expansion matching circuit is not connected to the matching circuit.
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42. A portable radio apparatus in accordance with claim 2, further comprising:
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a detector for detecting whether the antenna is in an expanded state in which the antenna is expanded; and
an expansion matching circuit impedance of which matches with the antenna in the expanded state in a particular frequency band when the expansion matching circuit is connected to the matching circuit;
wherein;
the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands;
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic;
the expansion matching circuit is connected to the matching circuit when the antenna is in the expanded state and a particular one of the frequency bands is selected; and
impedance of the antenna in the expanded state matches that of the matching circuit in a frequency band for which the expansion matching circuit is not connected to the matching circuit.
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43. A portable radio apparatus in accordance with claim 3, further comprising:
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a detector for detecting whether the antenna is in an expanded state in which the antenna is expanded; and
an expansion matching circuit impedance of which matches with the antenna in the expanded state in a particular frequency band when the expansion matching circuit is connected to the matching circuit;
wherein;
the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands;
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic;
the expansion matching circuit is connected to the matching circuit when the antenna is in the expanded state and a particular one of the frequency bands is selected; and
impedance of the antenna in the expanded state matches that of the matching circuit in a frequency band for which the expansion matching circuit is not connected to the matching circuit.
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44. A portable radio apparatus in accordance with claim 4, further comprising:
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a detector for detecting whether the antenna is in an expanded state in which the antenna is expanded; and
an expansion matching circuit impedance of which matches with the antenna in the expanded state in a particular frequency band when the expansion matching circuit is connected to the matching circuit;
wherein;
the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands;
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic;
the expansion matching circuit is connected to the matching circuit when the antenna is in the expanded state and a particular one of the frequency bands is selected; and
impedance of the antenna in the expanded state matches that of the matching circuit in a frequency band for which the expansion matching circuit is not connected to the matching circuit.
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45. A portable radio apparatus in accordance with claim 5, further comprising:
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a detector for detecting whether the antenna is in an expanded state in which the antenna is expanded; and
an expansion matching circuit impedance of which matches with the antenna in the expanded state in a particular frequency band when the expansion matching circuit is connected to the matching circuit;
wherein;
the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands;
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic;
the expansion matching circuit is connected to the matching circuit when the antenna is in the expanded state and a particular one of the frequency bands is selected; and
impedance of the antenna in the expanded state matches that of the matching circuit in a frequency band for which the expansion matching circuit is not connected to the matching circuit.
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46. A portable radio apparatus in accordance with claim 6, further comprising:
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a detector for detecting whether the antenna is in an expanded state in which the antenna is expanded; and
an expansion matching circuit impedance of which matches with the antenna in the expanded state in a particular frequency band when the expansion matching circuit is connected to the matching circuit;
wherein;
the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands;
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic;
the expansion matching circuit is connected to the matching circuit when the antenna is in the expanded state and a particular one of the frequency bands is selected; and
impedance of the antenna in the expanded state matches that of the matching circuit in a frequency band for which the expansion matching circuit is not connected to the matching circuit.
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47. A portable radio apparatus in accordance with claim 7, further comprising:
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a detector for detecting whether the antenna is in an expanded state in which the antenna is expanded; and
an expansion matching circuit impedance of which matches with the antenna in the expanded state in a particular frequency band when the expansion matching circuit is connected to the matching circuit;
wherein;
the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands;
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic;
the expansion matching circuit is connected to the matching circuit when the antenna is in the expanded state and a particular one of the frequency bands is selected; and
impedance of the antenna in the expanded state matches that of the matching circuit in a frequency band for which the expansion matching circuit is not connected to the matching circuit.
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48. A portable radio apparatus in accordance with claim 8, further comprising:
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a detector for detecting whether the antenna is in an expanded state in which the antenna is expanded; and
an expansion matching circuit impedance of which matches with the antenna in the expanded state in a particular frequency band when the expansion matching circuit is connected to the matching circuit;
wherein;
the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands;
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic;
the expansion matching circuit is connected to the matching circuit when the antenna is in the expanded state and a particular one of the frequency bands is selected; and
impedance of the antenna in the expanded state matches that of the matching circuit in a frequency band for which the expansion matching circuit is not connected to the matching circuit.
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50. A portable radio apparatus in accordance with claim 10, further comprising:
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a detector for detecting whether the antenna is in an expanded state in which the antenna is expanded; and
an expansion matching circuit impedance of which matches with the antenna in the expanded state in a particular frequency band when the expansion matching circuit is connected to the matching circuit;
wherein;
the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands;
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic;
the expansion matching circuit is connected to the matching circuit when the antenna is in the expanded state and a particular one of the frequency bands is selected; and
impedance of the antenna in the expanded state matches that of the matching circuit in a frequency band for which the expansion matching circuit is not connected to the matching circuit.
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2. A portable radio apparatus in accordance with claim 1, wherein:
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9. A portable radio apparatus, comprising:
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an antenna for transmitting and receiving a radio signal;
a radio circuit for decoding the radio signal received via the antenna and encoding a signal to be transmitted as a radio signal via the antenna; and
a matching circuit for providing an impedance match between the antenna and the radio circuit, the matching circuit including at least one capacitive element connected in parallel to the antenna. - View Dependent Claims (19, 29, 39, 49)
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19. A portable radio apparatus in accordance with claim 9, wherein:
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the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands; and
the antenna has different two resonance frequencies in one of the frequency bands.
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29. A portable radio apparatus in accordance with claim 9, wherein:
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the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands; and
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic.
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39. A portable radio apparatus in accordance with claim 9, further comprising:
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a detector for detecting whether the antenna is in an expanded state in which the antenna is expanded; and
an expansion matching circuit impedance of which matches with the antenna in the expanded state in a particular frequency band when the expansion matching circuit is connected to the matching circuit;
wherein;
the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands;
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic; and
the expansion matching circuit is connected to the matching circuit when the antenna is in the expanded state and a particular one of the frequency bands is selected.
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49. A portable radio apparatus in accordance with claim 9, further comprising:
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a detector for detecting whether the antenna is in an expanded state in which the antenna is expanded; and
an expansion matching circuit impedance of which matches with the antenna in the expanded state in a particular frequency band when the expansion matching circuit is connected to the matching circuit;
wherein;
the radio circuit is a circuit for decoding and encoding the radio signal in a plurality of frequency bands;
the antenna has different two resonance frequencies in one of the frequency bands;
the antenna includes a straight section and a helical section, the helical section having a two-resonance characteristic;
the expansion matching circuit is connected to the matching circuit when the antenna is in the expanded state and a particular one of the frequency bands is selected; and
impedance of the antenna in the expanded state matches that of the matching circuit in a frequency band for which the expansion matching circuit is not connected to the matching circuit.
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19. A portable radio apparatus in accordance with claim 9, wherein:
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Specification
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Current AssigneeLenovo Innovations Ltd Hong Kong (Lenovo Group Ltd.)
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Original AssigneeNEC Corporation
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InventorsSaito, Tetsuya
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Granted Patent
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Time in Patent OfficeDays
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Field of Search
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US Class Current343/860
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CPC Class CodesH01Q 1/244 extendable from a housing a...H03H 7/38 Impedance-matching networksH03H 7/46 Networks for connecting sev...H04B 1/005 adapting radio receivers, t...H04B 1/006 using switches for selectin...H04B 1/406 with more than one transmis...