# US 8,787,145 B2 · Area and power efficient architectures of time deinterleaver for receivers > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,787,145 B2 - Document ID: US8787145B2 - Status: Granted - Kind: B2 - Application number: 13/608,320 - Filed: 2012-09-10 - Published: 2013-01-03 - Granted: 2014-07-22 - Earliest claimed: 2008-01-16 - Assignees: Newport Media, Inc. - Applicants: Philip Treigherman - Inventors: Philip Treigherman - Web page: https://patentgrep.com/patent/US8787145B2 ## CPC - H04L 27/2647: {Arrangements specific to the receiver only (equalisation H04L27/01)} - H03M 13/2732: {Convolutional interleaver; Interleavers using shift-registers or delay lines like, e.g. Ramsey type interleaver} - H03M 13/276: {Interleaving address generation} - H03M 13/2789: {Interleaver providing variable interleaving, e.g. variable block sizes} - H04L 1/0052: {Realisations of complexity reduction techniques, e.g. pipelining or use of look-up tables} - H04L 1/0071: {Use of interleaving (interleaving per se H03M13/27)} - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) - H03M: CODING; DECODING; CODE CONVERSION IN GENERAL (using fluidic means F15C4/00; optical analogue/digital converters G02F7/00; coding, decoding or code conversion, specially adapted for particular applications, see the relevant subclasses, e.g. G01D, G01R, G06F, G06T, G09G, G10L, G11B, G11C, H04B, H04L, H04M, H04N; ciphering or deciphering for cryptography or other purposes involving the need for secrecy G09C) ## Abstract A method and apparatus for de-interleaving interleaved data in a deinterleaver memory in an Orthogonal Frequency Division Multiplexing (OFDM) based Integrated Services Digital Broadcasting Terrestrial (ISDB-T) receiver. In different embodiments, the apparatus comprises of a OFDM symbol counter along with a divider or a buffer pointer RAM with circular pointer logic, a first lookup table to obtain delay buffer size and interleaving lengths for a given OFDM transmission layer, and a second lookup table to obtain buffer base address and interleaving lengths for a given OFDM transmission layer. ## Claims ### Claim 1 An apparatus for de-interleaving interleaved data in an Orthogonal Frequency Division Multiplexing (OFDM) based receiver, said apparatus comprising: a deinterleaver memory; an OFDM symbol counter incrementing once for each orthogonal frequency division multiplexing-OFDM symbol, wherein a bit width of said OFDM symbol counter is in the range of 23 to 33 bits; a divider for calculating intra buffer offset in said deinterleaver memory for every increment of said OFDM symbol counter; a first lookup table in said deinterleaver memory for obtaining delay buffer sizes for various carriers and interleaving lengths for a given OFDM transmission layer; and a second lookup table in said deinterleaver memory for obtaining buffer base addresses for various carriers and interleaving lengths for a given OFDM transmission layer, wherein said bit width of said OFDM symbol counter is selected based on uninterrupted television viewing time on a particular channel. ### Claim 2 (depends on 1) The apparatus of claim 1, wherein said divider comprises a combinational divider. ### Claim 3 (depends on 1) The apparatus of claim 1, wherein said divider comprises a sequential divider. ### Claim 4 (depends on 1) The apparatus of claim 1, wherein said first and second lookup tables are stored in a read-only memory (ROM). ### Claim 5 (depends on 1) The apparatus of claim 1, wherein said first and second lookup tables are implemented using dynamic arithmetic calculations. ### Claim 6 (depends on 1) The apparatus of claim 1, wherein said delay buffer sizes and said buffer base addresses are obtained from the first and second lookup tables for corresponding carriers and interleaving lengths for a given OFDM transmission layer. ### Claim 7 (depends on 1) The apparatus of claim 1, wherein said receiver comprises a mobile application receiver. ### Claim 8 (depends on 1) The apparatus of claim 1, wherein said receiver comprises a mobile television receiver. ### Claim 9 (depends on 1) The apparatus of claim 1, wherein said receiver comprises an Integrated Services Digital Broadcasting Terrestrial (ISDB-T) receiver. ### Claim 10 A method of deinterleaving interleaved data in a deinterleaver memory in an Orthogonal Frequency Division Multiplexing (OFDM) based receiver comprising a OFDM symbol counter, a divider, a first lookup table to obtain delay buffer size and interleaving lengths for a given OFDM transmission layer, and a second lookup table to obtain buffer base address and interleaving lengths for a given OFDM transmission layer, said method comprising: counting received OFDM symbols by incrementing said OFDM symbol counter, wherein said OFDM symbol counter comprises a bit width in the range of 23 to 33 bits; retrieving a delay buffer size value for a corresponding carrier from said first lookup table; calculating intra buffer offset by dividing said OFDM symbol counter with said delay buffer size of corresponding carrier; retrieving a buffer base address for corresponding carrier from said second lookup table; combining said intra buffer offset and said buffer base address to calculate a memory address to store corresponding carrier data bits; and storing said carrier data bits at said calculated memory address. ### Claim 11 (depends on 10) The method of claim 10, further comprising implementing the first and second lookup tables as a read-only memory (ROM). ### Claim 12 (depends on 10) The method of claim 10, further comprising implementing the first and second lookup tables as dynamic arithmetic calculations. ### Claim 13 (depends on 10) The method of claim 10, wherein said receiver comprises a mobile application receiver. ### Claim 14 (depends on 10) The method of claim 10, wherein said receiver comprises a mobile television receiver. ### Claim 15 (depends on 10) The method of claim 10, wherein said receiver comprises an Integrated Services Digital Broadcasting Terrestrial (ISDB-T) receiver. ### Claim 16 An Orthogonal Frequency Division Multiplexing (OFDM) based receiver that de-interleaves interleaved data, said receiver comprising: a deinterleaver memory; an OFDM symbol counter incrementing once for each orthogonal frequency division multiplexing-OFDM symbol, wherein a bit width of said OFDM symbol counter is in the range of 23 to 33 bits; a divider for calculating intra buffer offset in said deinterleaver memory for every increment of said OFDM symbol counter; a first lookup table in said deinterleaver memory for obtaining delay buffer sizes for various carriers and interleaving lengths for a given OFDM transmission layer; and a second lookup table in said deinterleaver memory for obtaining buffer base addresses for various carriers and interleaving lengths for a given OFDM transmission layer, wherein said bit width of said OFDM symbol counter is selected based on uninterrupted television viewing time on a particular channel. ### Claim 17 (depends on 16) The receiver of claim 16, wherein said divider comprises any of a combinational divider and a sequential divider. ### Claim 18 (depends on 16) The receiver of claim 16, further comprising a read-only memory (ROM) that stores said first and second lookup tables. ### Claim 19 (depends on 16) The receiver of claim 16, wherein said first and second lookup tables are implemented using dynamic arithmetic calculations. ### Claim 20 (depends on 16) The receiver of claim 16, wherein said delay buffer sizes and said buffer base addresses are obtained from the first and second lookup tables for corresponding carriers and interleaving lengths for a given OFDM transmission layer.