JPS5648746A - Fsk signal generating circuit - Google Patents

Fsk signal generating circuit

Info

Publication number
JPS5648746A
JPS5648746A JP12495279A JP12495279A JPS5648746A JP S5648746 A JPS5648746 A JP S5648746A JP 12495279 A JP12495279 A JP 12495279A JP 12495279 A JP12495279 A JP 12495279A JP S5648746 A JPS5648746 A JP S5648746A
Authority
JP
Japan
Prior art keywords
data
signal
frequency
fsk signal
rom
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.)
Granted
Application number
JP12495279A
Other languages
Japanese (ja)
Other versions
JPS6312424B2 (en
Inventor
Masakazu Tsuji
Hisaaki Azumaguchi
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.)
NEC Corp
Original Assignee
NEC Corp
Nippon Electric 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 NEC Corp, Nippon Electric Co Ltd filed Critical NEC Corp
Priority to JP12495279A priority Critical patent/JPS5648746A/en
Publication of JPS5648746A publication Critical patent/JPS5648746A/en
Publication of JPS6312424B2 publication Critical patent/JPS6312424B2/ja
Granted legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04L—TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00—Modulated-carrier systems
    • H04L27/10—Frequency-modulated carrier systems, i.e. using frequency-shift keying
    • H04L27/12—Modulator circuits; Transmitter circuits
    • H04L27/122—Modulator circuits; Transmitter circuits using digital generation of carrier signals

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Digital Transmission Methods That Use Modulated Carrier Waves (AREA)

Abstract

PURPOSE:To obtain an FSK signal of a frequency with no phase jump by storing ROM with different-frequency data that correspond to two kinds of logical values and change data between frequencies in the form of PCM data and then by A/D- converting them. CONSTITUTION:In ROM303, PCM data of the state of low frequency fL of an FSK signal, state changing from fL to high frequency fH, state of fH, and state changing of FH to FL are stored previously. Clock CL signal from terminal 1, transmitted data D from terminal 2 and delay transmitted data D' obtained by delaying 301 data D by one data period are received by address counter 302 and according to the address of counter 302, one of four states from ROM303 is selected and inputted to D/A converter 304. With signal CL, converter 304 converts the signal from ROM into a PAM signal, which is outputted via LPF305. The beginning and ending of foor PCM data stored in ROM are put in phase, so that an FSK signal having not any phase jump at a frequency change point can be obtained.
JP12495279A 1979-09-28 1979-09-28 Fsk signal generating circuit Granted JPS5648746A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP12495279A JPS5648746A (en) 1979-09-28 1979-09-28 Fsk signal generating circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP12495279A JPS5648746A (en) 1979-09-28 1979-09-28 Fsk signal generating circuit

Publications (2)

Publication Number Publication Date
JPS5648746A true JPS5648746A (en) 1981-05-02
JPS6312424B2 JPS6312424B2 (en) 1988-03-18

Family

ID=14898265

Family Applications (1)

Application Number Title Priority Date Filing Date
JP12495279A Granted JPS5648746A (en) 1979-09-28 1979-09-28 Fsk signal generating circuit

Country Status (1)

Country Link
JP (1) JPS5648746A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2511564A1 (en) * 1981-08-17 1983-02-18 Thomson Csf FREQUENCY SYNTHESIZER WITH FRACTIONARY DIVISION, USED FOR DIGITAL ANGULAR MODULATION
US4599583A (en) * 1983-11-19 1986-07-08 Fujitsu Limited Mixed dual frequency generating system
JPS61172464A (en) * 1985-01-25 1986-08-04 Tsubakimoto Chain Co Modulation circuit
JPH08125699A (en) * 1994-10-24 1996-05-17 Nec Corp Fsk modulator

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2511564A1 (en) * 1981-08-17 1983-02-18 Thomson Csf FREQUENCY SYNTHESIZER WITH FRACTIONARY DIVISION, USED FOR DIGITAL ANGULAR MODULATION
US4599583A (en) * 1983-11-19 1986-07-08 Fujitsu Limited Mixed dual frequency generating system
JPS61172464A (en) * 1985-01-25 1986-08-04 Tsubakimoto Chain Co Modulation circuit
JPH08125699A (en) * 1994-10-24 1996-05-17 Nec Corp Fsk modulator

Also Published As

Publication number Publication date
JPS6312424B2 (en) 1988-03-18

Similar Documents

Publication Publication Date Title
JPS5648746A (en) Fsk signal generating circuit
JPS55147060A (en) Fsk and psk modulating circuit
JPS5725755A (en) Waveform superposed fsk modulator
JPS52114256A (en) Phase synchronization circuit
JPS5232655A (en) Logic low-pass filter circuit
JPS5748849A (en) Digital phase modulator
JPS53131815A (en) Phase linear type emphasizer
JPS5378157A (en) Delta modulatio circuit
JPS5530274A (en) Digital mixer
JPS5317252A (en) Ssb modulator and demodulator
JPS5679524A (en) Conversion circuit for duty cycle
JPS5213757A (en) Sine wave signal generator circuit
JPS547841A (en) Variable frequency oscillator
JPS51146152A (en) Signal selection circuit
JPS55147062A (en) Frequency modulator
JPS5365648A (en) Digital fsk
JPS5742230A (en) Clock switching device
JPS5599826A (en) Phase variable circuit
JPS57135555A (en) Phase continuous fsk modulating circuit
JPS644128A (en) Pcm modulation demodulation circuit
JPS6436106A (en) Phase modulation circuit
JPS5625866A (en) Transmission system of communication signal
JPS5599825A (en) Phase variable circuit
JPS52100965A (en) Delta modulator
JPS5488753A (en) Digital level conversion system