DocumentCode :
3230425
Title :
A simple microcontroller based building block for digital communication applications
Author :
Sanyal, Salil K.
Author_Institution :
Dept. of Electron. & Telecommun. Eng., Jadavpur Univ., Calcutta, India
Volume :
2
fYear :
1998
fDate :
1998
Firstpage :
324
Abstract :
This paper describes the design of a simple building block for applications in the area of digital communication. The simple building block functions mainly as a digitally programmable oscillator (DPO) extendable to work as a BFSK modulator. The DPO is designed using an LM 565 PLL chip, the centre frequency of the VCO within which is controlled by an 8031 microcontroller using binary weighted switched programmable resistor array (BWSPRA) implemented by CMOS CD 4066 switches and binary weighted resistors. Good quality square and triangular waves were obtained from the block whose frequencies in the range of 90 kHz to 680 kHz were varied digitally. The incorporation of a sine shaper with the simple building block along with a buffer and amplifier provided sinusoidal DPO. In the design extension of the simple sinusoidal DPO to BFSK modulator the mark and the space frequencies were obtained by effectively switching a single resistor. The digital base band signal was a PN sequence of length 7 generated by the 8031 microcontroller. An assembly language program had been developed. Good quality BFSK output was obtained with good phase continuity
Keywords :
CMOS digital integrated circuits; assembly language; digital communication; digital phase locked loops; frequency shift keying; microcontrollers; modulators; programmable circuits; voltage-controlled oscillators; 8031 microcontroller; 90 to 680 kHz; BFSK modulator; CMOS CD 4066 switches; LM 565 PLL chip; MOS CD 4066 weighted resistors; PN sequence length; amplifier; assembly language program; binary weighted switched programmable resistor array; buffer; centre frequency; digital base band signal; digital communication applications; digitally programmable oscillator; mark frequency; microcontroller based building block; sine shaper; sinusoidal DPO; space frequency; square waves; triangular waves; Communication switching; Communication system control; Digital communication; Digital modulation; Frequency; Microcontrollers; Modulation coding; Phase locked loops; Resistors; Voltage-controlled oscillators;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
TENCON '98. 1998 IEEE Region 10 International Conference on Global Connectivity in Energy, Computer, Communication and Control
Conference_Location :
New Delhi
Print_ISBN :
0-7803-4886-9
Type :
conf
DOI :
10.1109/TENCON.1998.798151
Filename :
798151
Link To Document :
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