# US 10,122,528 B2 · Narrow band synchronization signal > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,122,528 B2 - Document ID: US10122528B2 - Status: Granted - Kind: B2 - Application number: 15/433,506 - Filed: 2017-02-15 - Published: 2017-11-02 - Granted: 2018-11-06 - Earliest claimed: 2016-04-29 - Assignees: QUALCOMM Incorporated - Applicants: QUALCOMM Incorporated - Inventors: Jing Lei; Peter Gaal; Hao Xu; Wanshi Chen; Xiao feng Wang - Web page: https://patentgrep.com/patent/US10122528B2 ## CPC - H04L 7/041: {using special codes as synchronising signal} - H04J 11/0076: {Acquisition of secondary synchronisation channel, e.g. detection of cell-ID group} - H04J 13/10: Code generation - H04J 13/107: {by concatenation} - H04W 48/16: Discovering, processing access restriction or access information - H04J 13/0062: {Zadoff-Chu} - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - 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) - H04W: WIRELESS COMMUNICATION NETWORKS (broadcast communication H04H; communication systems using wireless links for non-selective communication, e.g. wireless extensions H04M1/72) ## Abstract In order to address the needs of narrow band communication, eNB-based processing and/or UE-based processing is provided to achieve robust detection of cell ID and SFN timing location using NB-SSS. A base station constructs a NB-SSS signal using a root index of a Zadoff-Chu (ZC) sequence, a scrambling code, a cyclic shift or phase ramping sequence, and an interleaving sequence, wherein a combination of the ZC root index, the scrambling code index, the cyclic shift or phase ramping sequence index, and the interleaving sequence index signals information for a cell identifier (e.g., PCID) and frame timing. The ZC sequence used may be a long ZC sequence constructed to span a total number of tones allocated to an SSS sequence or may be a concatenation of multiple ZC sequences, wherein the concatenated ZC sequences span a total number of tones allocated to an SSS sequence. ## Claims ### Claim 1 A method of Narrow Band (NB) wireless communication, comprising: constructing a secondary synchronization signal (SSS) using a Zadoff-Chu (ZC) root index, a scrambling code, a cyclic shift or phase ramping sequence, and an interleaving sequence, wherein a combination of the ZC root index, the scrambling code index, the cyclic shift or phase ramping sequence index, and the interleaving sequence index signals information for a cell identifier (ID) and frame timing information, wherein constructing the SSS includes using a concatenation of multiple ZC sequences that span a total number of tones allocated to an SSS sequence and periodically permuting a root index and cyclic shift mapping; and transmitting the SSS using a NB. ### Claim 2 (depends on 1) The method of claim 1, wherein constructing the SSS includes constructing a ZC sequence that spans the total number of tones allocated to the SSS sequence. ### Claim 3 (depends on 2) The method of claim 2, wherein the ZC sequence is truncated or cyclically extended to fit the total number of tones allocated to the SSS sequence. ### Claim 4 (depends on 2) The method of claim 2, wherein the cell ID comprises a physical cell identifier. ### Claim 5 (depends on 1) The method of claim 1, wherein constructing the SSS includes applying an interleaver per symbol to a coded SSS sequence. ### Claim 6 (depends on 1) The method of claim 1, wherein constructing the SSS includes applying a binary or poly-phase code cover per symbol to a coded SSS sequence. ### Claim 7 (depends on 1) The method of claim 1, wherein constructing the SSS includes: using a mapping of at least one ZC root index and at least one cyclic shift, wherein the mapping is constructed based on error correction coding. ### Claim 8 (depends on 7) The method of claim 7, wherein an encoding alphabet used for the mapping includes using a code symbol alphabet, the code symbol alphabet comprising at least one of: a binary alphabet having 16 codewords; a binary alphabet having 4 codewords; an octa alphabet having 16 codewords; an octa alphabet having 4 codewords; a hexa alphabet having 16 codewords; or a hexa alphabet having 4 codewords. ### Claim 9 (depends on 7) The method of claim 7, wherein using the mapping includes mapping a code symbol alphabet to at least one of a plurality of sequence properties, the sequence properties including at least one of: a cyclic shift within a symbol in frequency; a cyclic shift within the symbol in time; selection of a sequence root; or scrambling across different symbols. ### Claim 10 (depends on 7) The method of claim 7, wherein input information for the SSS is mapped to information bits of the SSS using at least one of: a one-to-one structure; or a one-to-many structure. ### Claim 11 An apparatus for Narrow Band (NB) wireless communication, comprising: a memory; and at least one processor coupled to the memory and configured to: construct a secondary synchronization signal (SSS) using a Zadoff-Chu (ZC) root index, a scrambling code, a cyclic shift or phase ramping sequence, and an interleaving sequence, wherein a combination of the ZC root index, the scrambling code index, the cyclic shift or phase ramping sequence index, and the interleaving sequence index signals information for a cell identifier (ID) and frame timing information, wherein constructing the SSS includes using a concatenation of multiple ZC sequences that span a total number of tones allocated to an SSS sequence, and periodically permuting a root index and cyclic shift mapping; and transmit the SSS using a NB. ### Claim 12 (depends on 11) The apparatus of claim 11, wherein the at least one processor is further configured to construct a ZC sequence that spans the total number of tones allocated to the SSS sequence. ### Claim 13 (depends on 12) The apparatus of claim 12 wherein the ZC sequence is truncated or cyclically extended to fit the total number of tones allocated to the SSS sequence. ### Claim 14 (depends on 12) The apparatus of claim 12, wherein the cell ID comprises a physical cell ID. ### Claim 15 (depends on 11) The apparatus of claim 11, wherein the at least one processor is further configured to apply an interleaver per symbol to a coded SSS sequence. ### Claim 16 (depends on 11) The apparatus of claim 11, wherein the at least one processor is further configured to apply a binary or poly-phase code cover per symbol to a coded SSS sequence. ### Claim 17 A method of wireless communication, comprising: receiving a secondary synchronization signal (SSS) comprising multiple symbols; and using cross-correlation at each symbol of the SSS to decode the SSS in order to determine a cell identifier (ID) and frame timing information, wherein the cell ID and the frame timing information are determined based on a combination of a Zadoff-Chu (ZC) root index, a scrambling code index, a cyclic shift or phase ramping sequence index, and an interleaving sequence index used to construct the SSS, and wherein the SSS is constructed by a concatenation of multiple ZC sequences that span a total number of tones allocated to an SSS sequence and by periodically permuting a root index and cyclic shift mapping. ### Claim 18 (depends on 17) The method of claim 17, further comprising: using hypothesis testing for a plurality of hypotheses to decode the SSS; and using coding or mapping constraints to reduce a number of the plurality of hypotheses to be tested. ### Claim 19 (depends on 18) The method of claim 18, wherein an SSS-based processing is used to select a subset of the plurality of hypotheses for the hypothesis testing, the SSS-based processing comprising calculating a cross-correlation for each of a plurality of candidate SSS sequences for different System Frame Numbers (SFNs) at a plurality of boundaries within a time interval. ### Claim 20 (depends on 19) The method of claim 19, further comprising: indexing the calculated cross correlations; comparing a pattern of the indexed cross correlations; and selecting the subset of the plurality of hypotheses based on a relationship to an SSS mapping table. ### Claim 21 (depends on 18) The method of claim 18, wherein physical broadcast channel (PBCH) processing is used to select a subset of the plurality of hypotheses for the hypothesis testing. ### Claim 22 (depends on 21) The method of claim 21, wherein the PBCH processing comprises: comparing a PBCH decoding result for different System Frame Number (SFN) timing hypotheses; and selecting the subset of the plurality of hypotheses based on a relationship to the PBCH decoding result. ### Claim 23 An apparatus for wireless communication, comprising: a memory; and at least one processor coupled to the memory and configured to: receive a secondary synchronization signal (SSS) comprising multiple symbols; and use cross-correlation at each symbol of the SSS to decode the SSS in order to determine a cell identifier (ID) and frame timing information, wherein the cell ID and the frame timing information are determined based on a combination of a Zadoff-Chu (ZC) root index, a scrambling code index, a cyclic shift or phase ramping sequence index, and an interleaving sequence index used to construct the SSS, and wherein the SSS is constructed by a concatenation of multiple ZC sequences that span a total number of tones allocated to an SSS sequence and by periodically permuting a root index and cyclic shift mapping. ### Claim 24 (depends on 23) The apparatus of claim 23, wherein the at least one processor is further configured to: use hypothesis testing for a plurality of hypotheses to decode the SSS; and use coding or mapping constraints to reduce a number of the plurality of hypotheses to be tested. ### Claim 25 (depends on 24) The apparatus of claim 24, wherein a subset of the plurality of hypotheses for the hypothesis testing are selected based on at least one of SSS-based processing and physical broadcast channel (PBCH) processing.