US 11,817,632 B2
Circuit for optoelectronic down-conversion of THz signals
Peter Offermans, Zaltbommel (NL); Davide Guermandi, Heverlee (BE); and Ashwyn Srinivasan, Heverlee (BE)
Assigned to Imec vzw, Leuven (BE); and Stichting IMEC Nederland, Eindhoven (NL)
Filed by IMEC VZW, Leuven (BE); and Stichting IMEC Nederland, Eindhoven (NL)
Filed on Sep. 3, 2021, as Appl. No. 17/466,908.
Claims priority of application No. 20194884 (EP), filed on Sep. 7, 2020.
Prior Publication US 2022/0077603 A1, Mar. 10, 2022
Int. Cl. H01Q 23/00 (2006.01); H01Q 9/28 (2006.01)
CPC H01Q 23/00 (2013.01) [H01Q 9/285 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A circuit for optoelectronic down-conversion of a terahertz, THz, signal, the circuit comprising:
a first photodiode and a second photodiode configured to be excited by an optical beat signal; and
a common antenna, wherein the photodiodes are coupled in series through the common antenna, wherein terminals of the antenna are configured to form an output terminal, and the antenna is configured to receive the terahertz, THz, signal,
wherein the photodiodes thereby, via the optical beat signal, respectively down-convert the THz signal and generate a current comprising an intermediate frequency, IF, component and a direct current, DC, component, wherein the respective generated currents are summed at the output terminal, thereby obtaining the IF components and cancelling the DC components.