The paper present the RF transmitter architecture based on All Digital Phase Locked
Loop (ADPLL) which is built from the ground up using digital techniques and digital
creation flow. In this paper, we described a system on chip that integrates ADSP with a multi Gega-Hertz digital RF transmitter that meets the blue tooth specifications.

A need has arisen to find digital architectural solutions to the RF functions. The frequency synthesizer is a key block used for frequency translation of radio signals and has been traditionally based on a charge -pump phase-locked loop (PLL), which is not easily amenable to integration. Recently, a digitally -controlled oscillator (DCO), which deliberately avoids any analog tuning controls, was first presented for RF wireless applications. This allows for its loop control circuitry to be implemented in a fully digital manner as first proposed.
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