Abstract: Using the kernel density estimation method, a stochastic analysis of the performance of distributed transmit beamforming (DTBF) in the presence of node oscillator error is conducted. Considering carrier initial phase offset, carrier frequency offset and phase noise, the corresponding average beampattern and complementary cumulative distribution function are derived. Then the degradation factor and beampattern characteristic parameters are adopted to analyze the influence of local oscillator errors on far-field beam performance. Theoretical analysis and simulation results show that local oscillator error can result in the degradation of DTBF performance, the decrease of average main lobe level, the widening of main lobe, the expansion of sidelobe region, and the emergence of high beampattern sidelobe. Over time, the local oscillator error accumulates gradually, which makes the degradation become bigger and the energy focused on the target location become less.

Key words: distributed transmit beamforming (DTBF); local oscillator error; kernel estimation method; average beampattern; complementary cumulative distribution function