US 12,456,995 B2
Multiband digital pre-distorter with reduced dimension requirements
S M Shahrear Tanzil, Ottawa (CA); Ashim Biswas, Sollentuna (SE); Leonard Rexberg, Hässelby (SE); and Yuecheng Yang, Täby (SE)
Assigned to TELEFONAKTIEBOLAGET LM ERICSSON (PUBL), Stockholm (SE)
Appl. No. 18/287,681
Filed by Telefonaktiebolaget LM Ericsson (publ), Stockholm (SE)
PCT Filed Apr. 22, 2021, PCT No. PCT/SE2021/050369
§ 371(c)(1), (2) Date Oct. 20, 2023,
PCT Pub. No. WO2022/225429, PCT Pub. Date Oct. 27, 2022.
Prior Publication US 2024/0364372 A1, Oct. 31, 2024
This patent is subject to a terminal disclaimer.
Int. Cl. H04B 1/04 (2006.01); H03F 1/32 (2006.01)
CPC H04B 1/0475 (2013.01) [H03F 1/3241 (2013.01); H04B 2001/0425 (2013.01)] 20 Claims
OG exemplary drawing
 
1. A method for operating a digital pre-distorter, (DPD) for an access node, the method comprising:
receiving a plurality of input signals, each from a respective frequency band, wherein each signal is of memory order M;
for each frequency band l=1, . . . , B of the frequency bands:
generating a plurality of pre-distorted signals for the frequency band l based on the plurality of input signals coming from all the B frequency bands and using Look-Up Tables (LUTs) according to which there is one LUT structure with LUT-based transforms per each combination of frequency band l=1, . . . , B and memory order m=0, . . . , M, wherein each of the LUT structures comprises combinations of LUTs of at most dimension B−q, where 1≤q<B; and
combining the plurality of pre-distorted signals for the frequency band to provide a combined pre-distorted signal for the frequency band.