In this paper, a wireless transmitter for digital data communications in the frequency of 1.8 ~ 1.9 GHz is designed and implemented.
First up conversion transmitter suitable for integration is used. this paper present design techniques for distortionless FM PLL modulator. Modulator is made of PLL, Buffer and VCO. FM PLL modulator's characteristic is measured by using simple communication theory.
A 103.68 MHz VCO and PLL system which has about 2.3 msec lock up time for very stable modulation are designed and implemented. This PLL system is used for second local signal of DECT transmitter. Transmitter power amplifier has 220 mW output power and it is enough to DECT standard.
For implementation, very small size PCB is made and all the experiments and measurements are made on this PCB. Also this DECT system is made for commercial product.
