Example of how an arbitrarily charged particle can radiate in the plasma frame and in the relativistically shifted frame when approaching an observer. We study five arbitrary emitted waves as a function of the frequency, wave number, emission angle, and emission power (per unit spatial angle). The particle oscillates at frequency ω₀ = 1 rad s⁻¹ and has an elementary charge. A, B, …, E denote five types of emitted waves (blue crosses) with the same frequency ω₀ and five wave numbers kc ≈ −0.966, −0.707, 0, 0.707, and 0.966 rad s⁻¹, both in the plasma reference frame. Top row: Plasma reference frame. Bottom row: Relativistically shifted reference frame with γ_s = 5. Left column: Positions of waves in ω − k space. Middle column: Positions as a function of frequency and their emission angle. Right column: Position denoted by arrows at the analytical emission function. Dashed black line: Light line ω = kc. Dash-dotted gray line: Frequencies ω₀. Black line: Analytically estimated electromagnetic emission by oscillating particle from Eq. B.5.