JPS57147343A - Cordless telephone set - Google Patents

Cordless telephone set

Info

Publication number
JPS57147343A
JPS57147343A JP56032318A JP3231881A JPS57147343A JP S57147343 A JPS57147343 A JP S57147343A JP 56032318 A JP56032318 A JP 56032318A JP 3231881 A JP3231881 A JP 3231881A JP S57147343 A JPS57147343 A JP S57147343A
Authority
JP
Japan
Prior art keywords
stage
modulation
signal
pilot signal
wave
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP56032318A
Other languages
Japanese (ja)
Inventor
Shozo Kirimoto
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Tokyo Sanyo Electric Co Ltd
Sanyo Electric Co Ltd
Sanyo Denki Co Ltd
Original Assignee
Tokyo Sanyo Electric Co Ltd
Sanyo Electric Co Ltd
Sanyo Denki Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Tokyo Sanyo Electric Co Ltd, Sanyo Electric Co Ltd, Sanyo Denki Co Ltd filed Critical Tokyo Sanyo Electric Co Ltd
Priority to JP56032318A priority Critical patent/JPS57147343A/en
Publication of JPS57147343A publication Critical patent/JPS57147343A/en
Pending legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M1/00—Substation equipment, e.g. for use by subscribers
    • H04M1/72—Mobile telephones; Cordless telephones, i.e. devices for establishing wireless links to base stations without route selection
    • H04M1/725—Cordless telephones
    • H04M1/72502—Cordless telephones with one base station connected to a single line

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Mobile Radio Communication Systems (AREA)

Abstract

PURPOSE:To prevent wiretapping by a third-party subordinate equipment by using an AM wave for encryptography by operating a master equipment only when a carrier is sent as the AM by a pilot signal simultaneously with an FM wave. CONSTITUTION:At a subordinate equipment, a carrier from an oscillator 4 is processed through the FM modulation and AM modulation of an FM modulating stage 5 and an AM modulating stage 15 with a pilot signal from an oscillator 3, and the resulting signal is transmitted from an antenna 7 through a carrier amplifying and outputting stage 6. At a master equipment connected to a telephone circuit, the received signal is applied to the 1st pilot signal detecting stage 18 through an AM detecting stage 16, and also to the 2nd pilot signal detecting stage 17 through an FM detecting stage 11 and if the resulting signal is coincident with the signal from the corresponding subordinate equipment, i.e., a prescribed signal processied by FM modulation and AM modulation, gate circuits 13' and 13 are opened to make connection with the telephone circuit through an amplifying stage 14. Thus, the AM modulation is carried out simultaneously with the FM modulation, and this AM wave is used for ''encryptography''.
JP56032318A 1981-03-05 1981-03-05 Cordless telephone set Pending JPS57147343A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP56032318A JPS57147343A (en) 1981-03-05 1981-03-05 Cordless telephone set

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP56032318A JPS57147343A (en) 1981-03-05 1981-03-05 Cordless telephone set

Publications (1)

Publication Number Publication Date
JPS57147343A true JPS57147343A (en) 1982-09-11

Family

ID=12355580

Family Applications (1)

Application Number Title Priority Date Filing Date
JP56032318A Pending JPS57147343A (en) 1981-03-05 1981-03-05 Cordless telephone set

Country Status (1)

Country Link
JP (1) JPS57147343A (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0165058A2 (en) * 1984-06-12 1985-12-18 James W. Crimmins Communication systems with portable units

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS506246U (en) * 1973-05-14 1975-01-22
JPS53131625A (en) * 1977-04-21 1978-11-16 Asahi Onkyo Wireless device for engine starter of automobile

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS506246U (en) * 1973-05-14 1975-01-22
JPS53131625A (en) * 1977-04-21 1978-11-16 Asahi Onkyo Wireless device for engine starter of automobile

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0165058A2 (en) * 1984-06-12 1985-12-18 James W. Crimmins Communication systems with portable units
EP0165058A3 (en) * 1984-06-12 1986-12-17 James W. Crimmins Communication systems with portable units

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