Solutions

Set of solutions of the problem of finding binary sequences with low PSL level

• 01 - canonical solution implemented on C++:
  • optimization: none;
  • portability: C++11;
  • build: make;
  • contribution: none.
• 02 - minimalistic solution implemented on pure C:
  • optimization:
    • skipped inverse-time sequences;
    • using lookup table for calculate number of bits.
  • portability: C11;
  • build: make;
  • contribution: none.
• 03 - minimalistic solution implemented on C with inline assembly;
  • optimization:
    • multithreading;
    • skipped inverse-time sequences;
    • skipped sequences based on the already calculated sidelobe level of current sequence.
  • portability: C++11;
  • build: cmake;
  • contribution:
    • version 6b7fa8fa499df80824719e8a9b91ab7f062015b8 was used to proving sequences with length from 2 up to 13;
    • version 94bdafaabff628a155202d223ae583bd09f1604b was used to finding and proving sequences with length from 28 up to 47;
    • version 94bdafaabff628a155202d223ae583bd09f1604b with manually defined PSL limit 3 was used to finding and proving sequences with length 48;
    • version 1a8ce91075600206622a40c10419653bee9ee62b was used to finding and proving sequences with length 49 and took about 3.25 days on Intel(R) Core(TM) i7-4700MQ CPU @ 2.40GHz.
    • version 6aaa9b65fb8e3312e0947b1828501b396940ee11 was used to finding and proving sequences with length 50 and took about 5.55 days on Intel(R) Core(TM) i7-4700MQ CPU @ 2.40GHz.
    • version 0ba60c98b2ee8ba25dd777486399a5fc0f4083d3 was used to finding and proving sequences with length 51 and took about 8.15 days on Intel(R) Core(TM) i7-4700MQ CPU @ 2.40GHz.
• 04 - yet another solution implemented on C++, the main idea is try to use optimization based on reusing of partial sum of convolution:
  • optimization:
    • skipped inverse-time sequences;
    • abort calculation of sidelobe level for specific shift using current partially sum;
    • reusing of partial sum of convolution;
    • skipped sequences based on the already calculated sidelobe level of current sequence with sertain shift.
  • portability: C++11;
  • build: make;
  • contribution: none.
• 07 - minimalistic solution implemented on C++ with std::bitset as storage of sequences:
  • optimization:
    • skipped inverse-time sequences.
    • skipped sequences based on the already calculated sidelobe level of current sequence.
  • portability: C++11;
  • build: make;
  • contribution: none.
• 08 - another implemented on C++ with std::bitset as storage of sequences and with random sequence generator:
  • optimization:
    • multithreading;
    • skipped inverse-time sequences.
  • portability: C++11;
  • build: make;
  • contribution:
    • version c94f282d1a1e4d10c62d23dce8a17d5cfd6187f6 was used to finding and proving one sequence with length 52 and took about 20 seconds on Intel(R) Core(TM) i7-4700MQ CPU @ 2.40GHz;
    • version 57356a4204033c7ef2e42a6d8875914a5b82f3d2 was used to finding and proving one sequence with length 53 and took about 2 minutes on Intel(R) Core(TM) i7-4700MQ CPU @ 2.40GHz.