Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
327 words
A terminal adapter for use in access from an analog signal equipment to ISDN (Integrated Services Digital Network), said analog signal equipment having a first and a second port for transmitting an outgoing analog signal and for receiving an incoming analog signal, respectively, and to be connected to a first and a second analog public telephone line, respectively, so as to use said first and said second analog public telephone lines as a transmitting line and a receiving line, respectively, and said ISDN including an ISDN subscriber's line to be connected to said terminal adapter, said ISDN subscriber's line transmitting a TDM (Time Division Multiplex) signal which comprises first and second communication information channels for conveying communication information and a control channel for conveying a control signal for data link establishment and call control, said terminal adapter comprising: input circuit means to be connected to said first port for receiving said outgoing analog signal as a received analog signal; analog-digital converting means coupled to said input circuit means for converting said received analog signal to an outgoing digital signal; interface circuit means to be connected to said ISDN subscriber's line for transmitting an outgoing TDM signal to and receiving an incoming TDM signal from said ISDN subscriber's line, said interface circuit means coupled to said analog-digital converting means for delivering said outgoing digital signal into a particular one of said first and said second communication information channels of said outgoing TDM signal, said interface circuit means deriving, as an incoming digital signal, a signal of the particular communication channel of the incoming TDM signal; digital-analog converting means coupled to said interface circuit means for converting said incoming digital signal into a converted analog signal; and output circuit means to be connected to said second port of said analog signal equipment and coupled to said digital-analog converting means for delivering said converted analog signal as said incoming analog signal to said second port of said analog signal equipment.
Claim 2
Dependent Claim
327 words
A terminal adapter for use in access from an analog signal equipment to ISDN (Integrated Services Digital Network), said analog signal equipment having a first and a second port for transmitting an outgoing analog signal and for receiving an incoming analog signal, respectively, and to be connected to a first and a second analog public telephone line, respectively, so as to use said first and said second analog public telephone lines as a transmitting line and a receiving line, respectively, and said ISDN including an ISDN subscriber's line to be connected to said terminal adapter, said ISDN subscriber's line transmitting a TDM (Time Division Multiplex) signal which comprises first and second communication information channels for conveying communication information and a control channel for conveying a control signal for data link establishment and call control, said terminal adapter comprising: input circuit means to be connected to said first port for receiving said outgoing analog signal as a received analog signal; analog-digital converting means coupled to said input circuit means for converting said received analog signal to an outgoing digital signal; interface circuit means to be connected to said ISDN subscriber's line for transmitting an outgoing TDM signal to and receiving an incoming TDM signal from said ISDN subscriber's line, said interface circuit means coupled to said analog-digital converting means for delivering said outgoing digital signal into a particular one of said first and said second communication information channels of said outgoing TDM signal, said interface circuit means deriving, as an incoming digital signal, a signal of the particular communication channel of the incoming TDM signal; digital-analog converting means coupled to said interface circuit means for converting said incoming digital signal into a converted analog signal; and output circuit means to be connected to said second port of said analog signal equipment and coupled to said digital-analog converting means for delivering said converted analog signal as said incoming analog signal to said second port of said analog signal equipment.
Claim 3
Dependent Claim
218 words
A terminal adapter as claimed in claim 1, said analog signal equipment sending out, as a call request, a first and a second selection signal through said first and said second ports, respectively, said terminal adapter further comprising: first detecting means coupled to said input circuit means for detecting said first selection signal to produce a first detected selection signal; second detecting means coupled to said output circuit means for detecting said second selection signal to produce a second detected selection signal; address converting means coupled to said first and said second detecting means for producing an ISDN telephone number signal corresponding to said first and said second detected selection signals; and control channel processing means coupled to said address converting means and responsive to said ISDN telephone number signal for producing a control channel signal as a call connection request, said control channel signal comprising said ISDN telephone number signal and a channel indicator representative of a particular one of said first and said second communication information channels to be connected; said interface circuit means coupled to said control channel processing means and responsive to said control channel signal for delivering said control channel signal into said control channel of said outgoing TDM signal, to thereby establish a virtual communication line on said particular communication information channel.
Claim 4
Dependent Claim
197 words
A terminal adapter as claimed in claim 2, wherein said interface circuit means derives, as an incoming control channel signal, said control channel from said incoming TDM signal to deliver said incoming control channel signal to said control channel processing means; and said control channel processing means decides whether or not said incoming control channel signal has a call setup signal and an ISDN subscriber's number signal assigned thereto, said control channel processing means producing a first and a second driving signal when said incoming control channel signal has said call setup signal and said ISDN subscriber's number signal, said terminal adapter further comprising: first ringing signal generating means coupled to said control channel processing means and to said input circuit means and responsive to said first driving signal for generating a first ringing signal to deliver said first ringing signal to said analog signal equipment through said first port; and second ringing signal generating means coupled to said control channel processing means and to said output circuit means and responsive to said second driving signal for generating a second ringing signal to deliver said second ringing signal to said analog signal equipment through said second port.