# US 10,122,556 B2 · Transmitter and receiver > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,122,556 B2 - Document ID: US10122556B2 - Status: Granted - Kind: B2 - Application number: 15/520,013 - Filed: 2015-09-07 - Published: 2017-11-16 - Granted: 2018-11-06 - Earliest claimed: 2014-11-13 - Assignees: Mitsubishi Electric Corporation - Applicants: Mitsubishi Electric Corporation - Inventors: Masatsugu Higashinaka - Web page: https://patentgrep.com/patent/US10122556B2 ## CPC - H04L 27/12: Modulator circuits; Transmitter circuits - H04L 27/10: Frequency-modulated carrier systems, i.e. using frequency-shift keying (H04L27/32 takes precedence) - H04L 27/14: Demodulator circuits; Receiver circuits - H04L 27/18: Phase-modulated carrier systems, i.e. using phase-shift keying (H04L27/32 takes 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 - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract A transmitter for use in a communication system uses a orthogonal modulation method, and the transmitter includes: an orthogonal sequence prescriber that prescribes association between orthogonal signals and information words determined on the basis of sizes of differences between information words of a plurality of mutually different information words and a probability of occurrence of decision errors between orthogonal signals of a plurality of mutually orthogonal signals; and a symbol mapper that, upon input of any of the information words, generates modulation symbols based on the orthogonal signals associated with the input information word according to the associations prescribed by the orthogonal sequence prescriber. ## Claims ### Claim 1 A transmitter comprising: an orthogonal sequence prescriber to prescribe association between information words and orthogonal signals based on sizes of differences between information words of a plurality of mutually different information words and an inter-signal point distance between orthogonal signals of a plurality of mutually orthogonal signals; and a symbol mapper to, upon inputting of any of the information words, generate modulation symbols based on the orthogonal signals associated with the input information words according to the associations prescribed by the orthogonal sequence prescriber, wherein among the combinations of the information words, the orthogonal sequence prescriber associates combinations for which the size of the difference is maximum with, among combinations of the orthogonal signals, combinations for which the inter-signal point distance is maximum. ### Claim 2 (depends on 1) The transmitter according to claim 1, wherein among the combinations of the information words, the orthogonal sequence prescriber associates combinations for which the size of the difference is minimum with, among the combinations of orthogonal signals, combinations for which the inter-signal point distance is minimum. ### Claim 3 (depends on 2) The transmitter according to claim 2, wherein the orthogonal signals are bi-orthogonally modulated; and among the combinations of the orthogonal signals, in each of the combinations for which the inter-signal point distance is minimum, the orthogonal signals have adjacent phase rotation amounts and are identical except for the phase rotation amounts. ### Claim 4 (depends on 1) The transmitter according to claim 1, wherein the orthogonal signals are bi-orthogonally modulated; and the transmitter further comprises a phase rotator that rotates phase of the modulation symbols generated by the symbol mapper by phase rotation amounts that differ from one another according to a transmission timing of the modulation symbols. ### Claim 5 (depends on 4) The transmitter according to claim 4, wherein the phase rotation amounts of phase rotation of the modulation symbols are determined according to the transmission timing and a number of phase states defined for the orthogonal signals. ### Claim 6 (depends on 1) The transmitter according to claim 1, wherein the orthogonal signals are bi-orthogonally modulated based on orthogonal frequency shift keying (FSK). ### Claim 7 (depends on 1) The transmitter according to claim 1, wherein the orthogonal signals are bi-orthogonally modulated using in two phases that are orthogonal in a complex plane based on orthogonal frequency shift keying (FSK) using at least two mutually different frequencies; and the orthogonal sequence prescriber associates the information words and the orthogonal signals such that: among the combinations of the orthogonal signals, in each of the combinations for which the inter-signal point distance is minimum, the orthogonal signals have adjacent phase rotation amounts and are identical except for the phase rotation amounts; and among the combinations of the information words, the combinations for which the size of the difference is minimum are associated with, among the combinations of orthogonal signals, the combinations for which the inter-signal point distance is minimum. ### Claim 8 A receiver comprising: a correlation processor to find a correlation between a plurality of orthogonal signals that are mutually orthogonal and an input signal obtained from a signal received from an opposing transmitter; and a determiner to: determine, based on the correlation found by the correlation processor, which of the orthogonal signals has been transmitted by the opposing transmitter, and restore an information word corresponding to a determined orthogonal signal based on an association between the information words and the orthogonal signals determined based on a size of differences between a plurality of mutually different information words and an inter-signal point distance between the orthogonal signals; wherein the association between the information words and the orthogonal signals is determined by at least one of the following: among the combinations of the information words, associating combinations for which the size of the difference is maximum with, among combinations of the orthogonal signals, combinations for which the inter-signal point distance is maximum; and among the combinations of the information words, associating combinations for which the size of the difference is minimum with, among the combinations of orthogonal signals, combinations for which the inter-signal point distance is minimum. ### Claim 9 (depends on 8) The receiver according to claim 8, wherein the orthogonal signals are bi-orthogonally modulated; and among the combinations of the orthogonal signals, in each of the combinations for which the inter-signal point distance is minimum, the orthogonal signals have adjacent phase rotation amounts and are identical except for the phase rotation amounts. ### Claim 10 (depends on 8) The receiver according to claim 8, wherein the orthogonal signals are bi-orthogonally modulated; the signal received from the opposing transmitter is a signal transmitted by the transmitter after rotating phase of modulation symbols by phase rotation amounts that differ from one another according to a transmission timing of the modulation symbols; and the receiver further comprises a phase rotator that rotates phase of the input signal obtained from the signal received from the opposing transmitter to cancel the phase rotated in the transmitter, and that inputs the phase-rotation-canceled signal to the correlation processor. ### Claim 11 (depends on 8) The receiver according to claim 8, wherein the orthogonal signals are bi-orthogonally modulated based on orthogonal frequency shift keying (FSK). ### Claim 12 A receiver, comprising: a correlation processor to find a correlation between a plurality of orthogonal signals that are mutually orthogonal and an input signal obtained from a signal received from an opposing transmitter; and a determiner to: determine, based on the correlation found by the correlation processor, which of the orthogonal signals has been transmitted by the opposing transmitter, and restore an information word corresponding to a determined orthogonal signal based on an association between the information words and the orthogonal signals determined based on a size of differences between a plurality of mutually different information words and a probability of occurrence of determination errors between the orthogonal signals; wherein the orthogonal signals are bi-orthogonally modulated; the signal received from the opposing transmitter is a signal transmitted by the transmitter after rotating phase of modulation symbols by phase rotation amounts that differ from one another according to a transmission timing of the modulation symbols; and the receiver further comprises a phase rotator that rotates phase of the input signal obtained from the signal received from the opposing transmitter to cancel the phase rotated in the transmitter, and that inputs the phase-rotation-canceled signal to the correlation processor.