Communication device

Claim 2

A communication device, comprising: cable channel connection means for connecting a cable channel having a DC current power supply; radio channel connection means for connecting a radio channel; inversion detection means for detecting a DC current flowing through the cable channel and supervising a direction of the DC current after a calling is made through the cable channel so as to determine if a receiving end has responded; dial-tone signal detection means for detecting a dial-tone signal transmitted through the radio channel in an off-hook state; connected channel detection means which determines that the cable channel is connected to said communication device when said inversion detection means detects the DC current flowing through the cable channel, while it determines that the radio channel is connected to said communication device when said dial-tone signal detection means detects the dial-tone signal; and switch means for switching an input/output path for a communication signal between said cable channel connection means and said radio channel connection means according to a result of detection by said connected channel detection means.

Claim 3

The communication device as set forth in claim 1, wherein said inversion detection means includes: light emitting means which emits light in response to the DC current from the DC current supply through the cable channel; and detecting signal output means for outputting a DC current detection signal indicating that the DC current is detected upon receiving light from said light emitting means to said connected channel detection means.

Claim 4

The communication device as set forth in claim 1, wherein: said switch means switches an input/output path for a communication signal to said cable channel connection means when said connected channel detection means detects that the cable channel is connected to said communication device irrespectively of whether or not the radio channel is connected.

Claim 5

The communication device as set forth in claim 1, wherein: said connected channel detection means includes determination result output means for outputting a result of determination as connection channel information to a terminal equipment which is to communicate with a cable network or a radio network through said communication device.

Claim 6

The communication device as set forth in claim 1, further comprising circuit closing means which opens and closes a circuit, wherein: said circuit closing means forms a closed circuit including the cable channel in its closed position; and said connected channel detection means controls said inversion detection means to detect an existence of the DC current flowing through said closing circuit in a closed position of said circuit closing means.

Claim 7

A communication device comprising: cable channel connection means for connecting a cable channel having a DC current power supply; radio channel connection means for connecting a radio channel; CPC signal detection means for detecting a DC current flowing through the cable channel and detecting a CPC signal based on a period in which a supply of the DC current is stopped; dial-tone signal detection means for detecting a dial-tone signal transmitted through the radio channel in an off-hook state; connected channel detection means which determines that the cable channel is connected to said communication device when said CPC signal detection means detects the DC current flowing through the cable channel, while it determines that the radio channel is connected to said communication device when said dial-tone signal detection means detects the dial-tone signal; and switch means for switching an input/output path for a communication signal between said cable channel connection means and said radio channel connection means according to a result of detection by said connected channel detection means.

Claim 8

A communication device comprising: cable channel connection means for connecting a cable channel having a DC current power supply; radio channel connection means for connecting a radio channel; CPC signal detection means for detecting a DC current flowing through the cable channel and detecting a CPC signal based on a period in which a supply of the DC current is stopped; dial-tone signal detection means for detecting a dial-tone signal transmitted through the radio channel in an off-hook state; connected channel detection means which determines that the cable channel is connected to said communication device when said CPC signal detection means detects the DC current flowing through the cable channel, while it determines that the radio channel is connected to said communication device when said dial-tone signal detection means detects the dial-tone signal; and switch means for switching an input/output path for a communication signal between said cable channel connection means and said radio channel connection means according to a result of detection by said connected channel detection means.

Claim 9

A communication system, comprising: cable channel connection means for connecting a cable channel having a DC current power supply; radio channel connection means for connecting a radio channel; inversion detection means for detecting a DC current flowing through the cable channel and supervising a direction of the DC current after a calling is made through the cable channel so as to determine if a receiving end has responded; dial-tone signal detection means for detecting a dial-tone signal transmitted through the radio channel in an off-hook state; connected channel detection means which determines that the cable channel is connected to said communication system when said inversion detection means detects the DC current flowing through the cable channel, while it determines that the radio channel is connected to said communication system when said dial-tone signal detection means detects the dial-tone signal; and switch means for switching an input/output path for a communication signal between said cable channel connection means and said radio channel connection means according to a result of detection by said connected channel detection means.

Claim 10

A communication system, comprising: cable channel connection means for connecting a cable channel having a DC current power supply; radio channel connection means for connecting a radio channel; inversion detection means for detecting a DC current flowing through the cable channel and supervising a direction of the DC current after a calling is made through the cable channel so as to determine if a receiving end has responded; dial-tone signal detection means for detecting a dial-tone signal transmitted through the radio channel in an off-hook state; connected channel detection means which determines that the cable channel is connected to said communication system when said inversion detection means detects the DC current flowing through the cable channel, while it determines that the radio channel is connected to said communication system when said dial-tone signal detection means detects the dial-tone signal; and switch means for switching an input/output path for a communication signal between said cable channel connection means and said radio channel connection means according to a result of detection by said connected channel detection means.

Claim 11

The communication system as set forth in claim 7 further comprising terminal equipment which includes: display means for displaying candidate protocols, so that a user may select a protocol desired enabling communication to be performed based on the selected protocol by the user.

Claim 12

A communication system comprising: cable channel connection means for connecting a cable channel having a DC current power supply; radio channel connection means for connecting a radio channel; CPC signal detection means for detecting a DC current flowing through the cable channel and detecting a CPC signal based on a period in which a supply of the DC current is stopped; dial-tone signal detection means for detecting a dial-tone signal transmitted through the radio channel in an off-hook state; connected channel detection means which determines that the cable channel is connected to said communication system when said CPC signal detection means detects the DC current flowing through the cable channel, while it determines that the radio channel is connected to said communication system when said dial-tone signal detection means detects the dial-tone signal; and switch means for switching an input/output path for a communication signal between said cable channel connection means and said radio channel connection means according to a result of detection by said connected channel detection means.

Claim 13

A communication system comprising: cable channel connection means for connecting a cable channel having a DC current power supply; radio channel connection means for connecting a radio channel; CPC signal detection means for detecting a DC current flowing through the cable channel and detecting a CPC signal based on a period in which a supply of the DC current is stopped; dial-tone signal detection means for detecting a dial-tone signal transmitted through the radio channel in an off-hook state; connected channel detection means which determines that the cable channel is connected to said communication system when said CPC signal detection means detects the DC current flowing through the cable channel, while it determines that the radio channel is connected to said communication system when said dial-tone signal detection means detects the dial-tone signal; and switch means for switching an input/output path for a communication signal between said cable channel connection means and said radio channel connection means according to a result of detection by said connected channel detection means.

Claim 14

The communication system as set forth in claim 9 further comprising terminal equipment which includes: display means for displaying candidate protocols, so that a user may select a protocol desired enabling communication to be performed based on the selected protocol by the user.

Claim 15

A communication system, comprising: cable channel connection means for connecting a cable channel having a DC current power supply; radio channel communication means for connecting a radio channel; hook state detection means for detecting an existence of a DC current flowing through the cable channel and detecting whether the cable channel is in an on-hook state or in an off-hook state; dial-tone signal detection means for detecting a dial-tone signal transmitted through the radio channel in the off-hook state; connected channel detection means which determines that the cable channel is connected to said communication device when said hook state detection means detects the DC current flowing through the cable channel, while determines that the radio channel is connected to said communication device when said dial-tone signal detection means detects the dial-tone signal; switch means for switching an input/output path for a communication signal between said cable channel connection means and said radio connection means according to a result of detection by said connected channel detection means; and terminal equipment that includes: display means for displaying candidate protocols, so that a user may select a protocol desired enabling communication to be performed based on the selected protocol by the user.

Claim 16

A communication system, comprising: cable channel connection means for connecting a cable channel having a DC current power supply; radio channel communication means for connecting a radio channel; hook state detection means for detecting an existence of a DC current flowing through the cable channel and detecting whether the cable channel is in an on-hook state or in an off-hook state; dial-tone signal detection means for detecting a dial-tone signal transmitted through the radio channel in the off-hook state; connected channel detection means which determines that the cable channel is connected to said communication device when said hook state detection means detects the DC current flowing through the cable channel, while determines that the radio channel is connected to said communication device when said dial-tone signal detection means detects the dial-tone signal; switch means for switching an input/output path for a communication signal between said cable channel connection means and said radio connection means according to a result of detection by said connected channel detection means; and terminal equipment that includes: display means for displaying candidate protocols, so that a user may select a protocol desired enabling communication to be performed based on the selected protocol by the user.