This thesis proposes a novel, all synthesized, Injection Locked Ring Oscillator (ILRO). It employs a digitally tunable oscillator and a pulse injection locking technique. The frequency tuning range of the free running oscillator is from 210 MHz to 1.8 GHz with a 1.1 volt power supply. The tuning range from 1.0 to 1.8 GHz can be achieved with 215 tuning steps with a maximum step size of 11.2 MHz, that is well within the worst case 75MHz (3rd sub-harmonic) and 32 MHz (9 th sub-harmonic) locking range of the oscillator.The design occupies 127.5 um by 31.5 um of chip area and is implemented in TSMC's 65nm CMOS technology. For 3rd harmonic injection locking, the ILRO's RMS jitter is 192.7 fs (1 KHz to 40 MHz) with a phase noise of -130.9 dBc/Hz at 1 MHz offset from the 1.62GHz carrier while consuming 7.15 mW of power.iii