US 12,470,297 B2
Photonic RF signal generation apparatus, network units and method
Alessandra Bigongiari, Pisa (IT); Antonio D'Errico, Pisa (IT); Antonio Malacarne, Pisa (IT); Marco Secondini, Pisa (IT); and Claudio Porzi, Pisa (IT)
Assigned to Telefonaktiebolaget LM Ericsson (Publ), Stockholm (SE)
Appl. No. 18/562,036
Filed by Telefonaktiebolaget LM Ericsson (publ), Stockholm (SE)
PCT Filed May 11, 2022, PCT No. PCT/EP2022/062857
§ 371(c)(1), (2) Date Nov. 17, 2023,
PCT Pub. No. WO2022/243140, PCT Pub. Date Nov. 24, 2022.
Claims priority of application No. PCT/EP2021/063285 (WO), filed on May 19, 2021.
Prior Publication US 2024/0235682 A1, Jul. 11, 2024
Int. Cl. H04B 10/2575 (2013.01); H04B 10/50 (2013.01)
CPC H04B 10/2575 (2013.01) [H04B 10/50 (2013.01)] 19 Claims
OG exemplary drawing
 
1. A photonic radio frequency, RF, signal generation apparatus comprising:
a coherent optical source operable to output a coherent optical signal at a carrier frequency, ƒ0;
an optical splitter arranged to split the coherent optical signal into a first optical carrier signal and a second optical carrier signal;
RF signal generation apparatus configured to generate at least one RF signal (V(t)) at an initial frequency, ƒe;
optical modulation apparatus driven by the at least one RF signal and configured to modulate the first optical carrier signal and the second optical carrier signal at the initial frequency to generate a plurality of optical harmonic signals around each optical carrier signal;
a first optical filter configured to select an nth order optical harmonic signal of a first sign, +n, of the plurality of optical harmonics around the first optical carrier signal;
a second optical filter configured to select the nth order optical harmonic signal of an opposite sign, −n, of the plurality of optical harmonics around the second optical carrier signal; and
an optical combiner arranged to combine the selected +n optical harmonic signal with the selected −n optical harmonic signal to generate an optical beat signal forming an output photonic RF signal; and
an optical delay apparatus arranged to apply a delay, τ, to optical signals, the optical delay apparatus being arranged to apply the delay to the first optical carrier signal before the first optical carrier signal is modulated by the optical modulation apparatus and to apply the delay to at least the −n optical harmonic signal before the optical combiner combines the −n optical harmonic signal with the selected +n optical harmonic signal.