# US 2021/0242952 A1 · Discontinuous time-frequency operation > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2021/0242952 A1 - Document ID: US20210242952A1 - Status: Published application - Kind: A1 - Application number: 17/142,994 - Filed: 2021-01-06 - Published: 2021-08-05 - Earliest claimed: 2020-01-31 - Assignees: Nokia Solutions and Networks Oy - Applicants: Nokia Solutions and Networks Oy - Inventors: Wouter LANNEER; Paschalis TSIAFLAKIS - Web page: https://patentgrep.com/patent/US20210242952A1 ## CPC - H04B 3/32: Reducing cross-talk, e.g. by compensating - H04J 1/12: Arrangements for reducing cross-talk between channels {(in line transmission systems H04B3/32; in cables or lines H04B3/26 - H04B3/30)} - H04J 11/00: Orthogonal multiplex systems, {e.g. using WALSH codes}(H04J13/00 takes precedence) - H04B: TRANSMISSION - H04J: MULTIPLEX COMMUNICATION (transmission in general H04B; peculiar to transmission of digital information H04L5/00; systems for the simultaneous or sequential transmission of more than one television signal H04N7/08; in exchanges H04Q11/00; stereophonic systems H04S) ## Abstract Example embodiments describe means (200) for performing i) pre-compensating (210, N sets of K1 tone data values (220) for crosstalk between N communication lines; the N sets of K1 tone data values pertaining to respective N terminal nodes of a digital communication system; ii) calculating (215) from the pre-compensated N sets of K1 tone data values (221) N sets of first time domain symbols (225); iii) calculating (283) a second time domain symbol (284) from a set of K2 tones values (280); the K2 tone data values pertaining to a selected one of the N terminal nodes; and iv) adding (212) the second time domain symbol in a weighted manner to the first time domain symbols such that the second time domain symbol is added to the first time domain symbol for the selected terminal node and to at least one other of the first time domain symbols for the respective other terminal nodes. ## Claims ### Claim 1 An apparatus comprising at least one processor and at least one memory including computer program code, the at least one memory and the computer program code configured to, with the at least one processor, cause the apparatus at least to perform: pre-compensating N sets of K1 tone data values for crosstalk between N communication lines; the N sets of K1 tone data values pertaining to respective N terminal nodes of a digital communication system; calculating from the pre-compensated N sets of K1 tone data values N sets of first time domain symbols; calculating a second time domain symbol from a set of K2 tone data values; the K2 tone data values pertaining to a selected one of the N terminal nodes; adding the second time domain symbol in a weighted manner to the first time domain symbols such that the second time domain symbol is added to the first time domain symbol for the selected terminal node and to at least one other of the first time domain symbols for the respective other terminal nodes. ### Claim 2 (depends on 1) The apparatus according to claim 1 wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus at least to further perform the adding according to weighting coefficients. ### Claim 3 (depends on 2) The apparatus according to claim 2 wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus at least to further perform selecting the weighting coefficients based on the selected one of the N terminal nodes. ### Claim 4 (depends on 2) The apparatus according to claim 2 wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus at least to further perform selecting the selected one of the N terminal nodes based on throughput requirements. ### Claim 5 (depends on 2) The apparatus according to claim 2 wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus at least to further perform selecting the weighting coefficients from one of the groups: {0; 1}; {1; −1}; or {1}. ### Claim 6 (depends on 2) The apparatus according to claim 2 wherein all weighting coefficients are equal. ### Claim 7 (depends on 2) The apparatus according to claim 2 wherein the second time domain symbol is complex and the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus at least to further perform adding according to complex weighting coefficients. ### Claim 8 (depends on 7) The apparatus according to claim 7 wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus at least to further perform selecting complex weighting coefficients from a group of numbers comprising 1, −1, j and −j. ### Claim 9 (depends on 8) The apparatus according to claim 8 wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus at least to further perform selecting complex weighting coefficients such that a rotation of the second time domain symbol is performed in the complex plane. ### Claim 10 (depends on 1) The apparatus according to claim 1 wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus at least to further perform calculating the N sets of first time domain symbols by performing a frequency to time domain conversion and an upsampling. ### Claim 11 (depends on 1) The apparatus according to claim 1 wherein the at least one memory and the computer program code are further configured to, with the at least one processor, cause the apparatus at least to further perform adding (212, 412) the second time domain symbol in a weighted manner by performing at least one of a bit shifting operation on the second time domain symbol, a sign switching operation on the second time domain symbol, or a swapping between a real and imaginary component of the second time domain symbol such that a weighting is achieved; and adding at least one of the shifted, the sign switched, or the swapped second time domain symbol to the respective one of the first time domain symbols. ### Claim 12 (depends on 1) The apparatus according to claim 1, wherein said apparatus is comprised in an access node for a telecommunications network. ### Claim 13 (depends on 2) The apparatus according to claim 2, wherein said apparatus is comprised in an access node for a telecommunications network. ### Claim 14 A method comprising: pre-compensating (210, 310, 410) N sets of K1 tone data values (220, 240, 260) for crosstalk between N communication lines (131-137); the N sets of K1 tone data values pertaining to respective N terminal nodes (111, 117) of a digital communication system; calculating (215, 322, 324, 422, 424) from the pre-compensated N sets of K1 tone data values (221, 321, 421) N sets of first time domain symbols (225, 325, 425); calculating (283, 383, 483) a second time domain symbol (284, 384, 484) from a set of K2 tones values (280, 380, 480); the K2 tone data values pertaining to a selected one of the N terminal nodes; adding (212, 312, 412) the second time domain symbol in a weighted manner to the first time domain symbols such that the second time domain symbol is added to the first time domain symbol for the selected terminal node and to at least one other of the first time domain symbols for the respective other terminal nodes. ### Claim 15 (depends on 14) The method according to claim 14 further comprising performing the adding according to weighting coefficients ### Claim 16 A non-transitory computer readable medium comprising program instructions for causing an apparatus to perform at least the following: pre-compensating (210, 310, 410) N sets of K1 tone data values (220, 240, 260) for crosstalk between N communication lines (131-137); the N sets of K1 tone data values pertaining to respective N terminal nodes (111, 117) of a digital communication system; calculating (215, 322, 324, 422, 424) from the pre-compensated N sets of K1 tone data values (221, 321, 421) N sets of first time domain symbols (225, 325, 425); calculating (283, 383, 483) a second time domain symbol (284, 384, 484) from a set of K2 tones values (280, 380, 480); the K2 tone data values pertaining to a selected one of the N terminal nodes; adding (212, 312, 412) the second time domain symbol in a weighted manner to the first time domain symbols such that the second time domain symbol is added to the first time domain symbol for the selected terminal node and to at least one other of the first time domain symbols for the respective other terminal nodes. ### Claim 17 A non-transistory computer readable medium comprising program instructions stored thereon for performing at least the following: pre-compensating (210, 310, 410) N sets of K1 tone data values (220, 240, 260) for crosstalk between N communication lines (131-137); the N sets of K1 tone data values pertaining to respective N terminal nodes (111, 117) of a digital communication system; calculating (215, 322, 324, 422, 424) from the pre-compensated N sets of K1 tone data values (221, 321, 421) N sets of first time domain symbols (225, 325, 425); calculating (283, 383, 483) a second time domain symbol (284, 384, 484) from a set of K2 tones values (280, 380, 480); the K2 tone data values pertaining to a selected one of the N terminal nodes; adding (212, 312, 412) the second time domain symbol in a weighted manner to the first time domain symbols such that the second time domain symbol is added to the first time domain symbol for the selected terminal node and to at least one other of the first time domain symbols for the respective other terminal nodes.