# US 9,882,659 B2 · Adaptive symbol mapping > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,882,659 B2 - Document ID: US9882659B2 - Status: Granted - Kind: B2 - Application number: 15/670,142 - Filed: 2017-08-07 - Published: 2017-11-23 - Granted: 2018-01-30 - Earliest claimed: 2015-12-14 - Assignees: Maxlinear Asia Singapore PTE LTD - Applicants: Maxlinear Asia Singapore PTE LTD - Inventors: Nadav Fine; Ran Soffer - Web page: https://patentgrep.com/patent/US9882659B2 ## CPC - H04B 14/02: characterised by the use of pulse modulation (in radio transmission relays H04B7/17) - H04B 14/004: {Amplitude modulation} - H04B 14/023: {using pulse amplitude modulation} - H04L 1/0042: {Encoding specially adapted to other signal generation operation, e.g. in order to reduce transmit distortions, jitter, or to improve signal shape (H04L1/0067 takes precedence)} - H04L 1/0045: {Arrangements at the receiver end} - H04L 1/007: {Unequal error protection (for format H04L1/0078; for codes per se H03M13/35)} - H04L 27/0008: {arrangements for allowing a transmitter or receiver to use more than one type of modulation (negotiating modulation type for two-way transmission paths H04L5/1453)} - H04L 27/3411: {reducing the peak to average power ratio or the mean power of the constellation; Arrangements for increasing the shape gain of a signal set} - H04L 43/028: by filtering - H04L 43/16: Threshold monitoring - H04W 24/02: Arrangements for optimising operational condition - H04L 1/0065: {Serial concatenated codes} - H04B: TRANSMISSION - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract The continuous demand for capacity and the limited available spectrum in wireless and wired communication has led to reliance on advanced modulation techniques to dramatically increase the number of bits per hertz per second. This demand in capacity and using the higher order constellations shorten the link range, and as a result, system gain becomes an important characteristic. The modulation techniques described here improve the system gain by, e.g., as much as 2.5 dB in high order modulations such as 4096-QAM. The modulation techniques include reducing the peak to average ratio and adding shaping gain. These techniques dramatically improve the system capacity, system gain, power consumption and system cost. ## Claims ### Claim 1 A method comprising: a receiving source data to be modulated into a transmit signal; mapping the source data to: a nominal modulation constellation symbol for the source data; and an alternate modulation constellation symbol for the source data; receiving signal peak feedback with respect to the transmit signal; and selecting, responsive to the signal peak feedback, between the nominal modulation constellation symbol and the alternate modulation constellation symbol for shaping the transmit signal. ### Claim 2 (depends on 1) The method of claim 1, where selecting comprises: selecting the alternate constellation symbol when the signal peak feedback exceeds a pre-determined feedback threshold. ### Claim 3 (depends on 1) The method of claim 1, where mapping comprises: applying a binary code to at least a portion of the source data. ### Claim 4 (depends on 1) The method of claim 1, where: mapping further comprises encoding a specific bit arising from the source data to obtain an encoded bit. ### Claim 5 (depends on 4) The method of claim 4, comprising: determining the nominal modulation constellation symbol and the alternate modulation constellation symbol according to the encoded bit. ### Claim 6 (depends on 5) The method of claim 5, where: encoding comprises binary encoding the specific bit. ### Claim 7 (depends on 1) The method of claim 1, comprising: determining a candidate version of the transmit signal; and analyzing the candidate version of the transmit signal for a signal peak. ### Claim 8 (depends on 7) The method of claim 7, where: determining comprises applying a shaping filter to a candidate symbol for the transmit signal. ### Claim 9 (depends on 1) The method of claim 1, comprising: splitting the source data into a first layer bit stream and a second layer bit stream; coding the first layer bit stream and the second layer bit stream in different ways to obtain different coding input streams; and determining a candidate version of the transmit signal based on a combination of the different coding input streams. ### Claim 10 (depends on 9) The method of claim 9, comprising: determining the signal peak feedback based on a signal peak in the candidate version of the transmit signal. ### Claim 11 A system comprising: a receiver operable to receive source data to be modulated into a transmit signal; a symbol mapper operable to map the source data to a nominal modulation constellation symbol and an alternate modulation constellation symbol; a peak locator operable to receive signal peak feedback with respect to the transmit signal; and a symbol selector operable to select, responsive to the signal peak feedback, between the nominal modulation constellation symbol and the alternate modulation constellation symbol for shaping the transmit signal. ### Claim 12 (depends on 11) The system of claim 11, wherein the symbol selector is operable to select the alternate constellation symbol when the signal peak feedback exceeds a pre-determined feedback threshold. ### Claim 13 (depends on 11) The system of claim 11, wherein the symbol mapper is operable to apply a binary code to at least a portion of the source data. ### Claim 14 (depends on 11) The system of claim 11, wherein the symbol mapper is operable to encode a specific bit arising from the source data to obtain an encoded bit. ### Claim 15 (depends on 14) The system of claim 14, wherein the symbol mapper is operable to determine the nominal modulation constellation symbol and the alternate modulation constellation symbol according to the encoded bit. ### Claim 16 (depends on 15) The system of claim 15, wherein the symbol mapper is operable to binary encode the specific bit. ### Claim 17 (depends on 11) The system of claim 11, wherein the peak locator is operable to determine a candidate version of the transmit signal and analyze the candidate version of the transmit signal for a signal peak. ### Claim 18 (depends on 17) The system of claim 17, wherein the symbol selector is operable to apply a shaping filter to a candidate symbol for the transmit signal. ### Claim 19 (depends on 11) The system of claim 11, wherein the system comprises: a bit splitter operable to split the source data into a first layer bit stream and a second layer bit stream; and an encoder operable to code the first layer bit stream and the second layer bit stream in different ways to obtain different coding input streams; and wherein the symbol mapper is operable to determine a candidate version of the transmit signal based on a combination of the different coding input streams. ### Claim 20 (depends on 19) The system of claim 19, wherein the peak locator is operable to determine the signal peak feedback based on a signal peak in the candidate version of the transmit signal.