# US 11,444,814 B2 · Innovative use of the kalman filter in reception matrices for perfoming an improved estimation of telecommunication signals > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,444,814 B2 - Document ID: US11444814B2 - Status: Granted - Kind: B2 - Application number: 17/043,351 - Filed: 2018-03-30 - Published: 2021-01-28 - Granted: 2022-09-13 - Earliest claimed: 2018-03-30 - Assignees: Eutelsat S A - Applicants: Eutelsat S A - Inventors: Jacques Dutronc; Antonio Saitto - Web page: https://patentgrep.com/patent/US11444814B2 ## CPC - H04L 27/2334: {using filters} - H04L 25/0384: {Design of pulse shapes (pulse shape for impulse radio H04B1/7172)} - H04L 27/2335: {using temporal properties of the received signal} - H04L 27/2338: {using sampling (H04L27/2331 - H04L27/2335 take precedence)} - H04L 27/32: Carrier systems characterised by combinations of two or more of the types covered by groups H04L27/02, H04L27/10, H04L27/18 or H04L27/26 - H04B 1/69: Spread spectrum techniques - H04L 5/04: the signals being represented by different amplitudes or polarities, e.g. quadriplex - H04L 27/18: Phase-modulated carrier systems, i.e. using phase-shift keying (H04L27/32 takes precedence) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04B: TRANSMISSION ## Abstract A radio communications method includes carrying out, by a transmitter, transmission operations that include generating digital transmission signals carrying symbols to be transmitted and having a predefined time length; and transmitting a radio frequency signal carrying, in successive, non-overlapped time frames or slots having the predefined time length, the digital transmission signals generated. The method further includes carrying out, by a receiver, reception operations that include receiving the radio frequency signal transmitted by the transmitter; processing the received radio frequency signal to obtain a corresponding digital incoming signal; applying an oversampling operation to the digital incoming signal thereby obtaining an oversampled digital incoming signal; detecting successive, non-overlapped time frames/slots with the predefined time length in the oversampled digital incoming signal; and, for each detected time frame/slot, estimating respective symbols carried by the oversampled digital incoming signal in the time frame/slot with a predefined reception matrix incorporating a predefined Kalman filter. ## Claims ### Claim 1 A radio communications method including carrying out, by a transmitter, transmission operations that comprise: generating digital transmission signals carrying symbols to be transmitted and having a predefined time length; and transmitting a radio frequency signal carrying, in successive, non-overlapped time frames or slots having the predefined time length, the digital transmission signals generated; the radio communications method further including carrying out, by a receiver, reception operations that comprise: receiving the radio frequency signal transmitted by the transmitter; processing the received radio frequency signal so as to obtain a corresponding digital incoming signal; applying an oversampling operation to the digital incoming signal thereby obtaining an oversampled digital incoming signal; detecting successive, non-overlapped time frames/slots with the predefined time length in the oversampled digital incoming signal; and, for each detected time frame/slot, estimating respective symbols carried by the oversampled digital incoming signal in said time frame/slot by using a predefined reception matrix, wherein the predefined reception matrix incorporates a static and non-iterative Kalman filter based on predefined or estimated noise levels related to radio communication carried out by the transmitter and the receiver. ### Claim 2 (depends on 1) The radio communications method of claim 1, wherein the digital transmission signals are generated by using one of the following digital transmission techniques: a predefined raised-cosine-filter-based technique, a predefined code-division technique, or a predefined frequency-division technique. ### Claim 3 (depends on 2) The radio communications method of claim 2, wherein the radio frequency signal is transmitted through a satellite transponder. ### Claim 4 (depends on 1) The radio communications method according to claim 1, wherein the generated digital transmission signals carry: first symbols via a first phase, or amplitude and phase, digital modulation related to an Orbital Angular Momentum mode with topological charge equal to zero; and second symbols via a second phase, or amplitude and phase, digital modulation related to one or more Orbital Angular Momentum modes with topological charge different than zero. ### Claim 5 (depends on 4) The radio communications method of claim 4, wherein the first and second phase, or amplitude and phase, digital modulations are performed in time or frequency domain. ### Claim 6 (depends on 1) A radio communications system comprising a transmitter and a receiver configured to carry out, respectively, the transmission and the reception operations of the radio communications method as defined in claim 1. ### Claim 7 (depends on 1) A transmitting and receiving equipment configured to carry out the transmission operations and the reception operations of the radio communications method as defined in claim 1. ### Claim 8 (depends on 1) A transmitting equipment configured to carry out the transmission operations of the radio communications method as defined in claim 1. ### Claim 9 (depends on 1) A receiving equipment configured to carry out the reception operations of the radio communications method as defined in claim 1. ### Claim 10 A radio communications method including carrying out, by a transmitter, transmission operations that comprise: generating digital transmission signals carrying symbols to be transmitted and having a predefined time length, wherein the generated digital transmission signals carry: first symbols via a first phase, or amplitude and phase, digital modulation related to an Orbital Angular Momentum mode with topological charge equal to zero; and second symbols via a second phase, or amplitude and phase, digital modulation related to one or more Orbital Angular Momentum modes with topological charge different than zero; and transmitting a radio frequency signal carrying, in successive, non-overlapped time frames or slots having the predefined time length, the digital transmission signals generated; the radio communications method further including carrying out, by a receiver, reception operations that comprise: receiving the radio frequency signal transmitted by the transmitter; processing the received radio frequency signal so as to obtain a corresponding digital incoming signal; applying an oversampling operation to the digital incoming signal thereby obtaining an oversampled digital incoming signal; detecting successive, non-overlapped time frames/slots with the predefined time length in the oversampled digital incoming signal; and, for each detected time frame/slot, estimating respective symbols carried by the oversampled digital incoming signal in said time frame/slot by using a predefined reception matrix incorporating a predefined Kalman filter.