Transmission of synchronization signals
Technology for a Next Generation NodeB (gNB) operable to encode a primary synchronization signal for transmission to a user equipment (UE) is disclosed. The gNB can identify a sequence d(n) for a primary synchronization signal. The sequence d(n) can be defined by: d(5 n)=1.2s(n), where s(n) is a maximum run length sequence (msequence) and s(n) is provided as s(n+7)=(s(n +4)+s(n)) mod 2, where 0.n.127. The gNB can generate the primary synchronization signal based on the sequence d(n). The gNB can encode the primary synchronization signal for transmission to the UE.
1. A base station operable to encode synchronization signals for transmission to a user equipment (UE), the base station comprising:
one or more processors configured to:
generate, at the base station, a binary sequence;
modulate, at the base station, the binary sequence using one or more modulation schemes to form a modulated binary sequence;
perform, at the base station, one of an extension or truncation operation on the modulated binary sequence to obtain a modulated binary sequence that is equal to a discrete Fourier transform (DFT) length of N, wherein N is an integer;
perform a multiplication operation to the modulated binary sequence, wherein the multiplication operation involves multiplying the modulated binary sequence with an alternating sequence of {+1, +j} that is mapped to even or odd subcarriers in the frequency domain;
perform, at the base station, a DFT operation to map the modulated binary sequence equal of DFT length N to N subcarriers in a frequency domain;
perform, at the base station, an inverse DFT operation to the modulated binary sequence equal to DFT length N that is mapped to the N subcarriers in the frequency domain to obtain synchronization signal (SS) orthogonal frequency division multiplexing (OFDM) symbols in a time domain; and
encode, at the base station, the SS OFDM symbols for transmission to the UE; and
a memory interface configured to retrieve from a memory the SS OFDM symbols.
2. The base station of claim 1 , further comprising a transceiver configured to transmit the SS OFDM symbols to the UE.
3. The base station of claim 1 , wherein the SS OFDM symbols form a primary synchronization signal.
4. The base station of claim 1 , wherein the one more processors are configured to generate the binary sequence based on an m-sequence that is generated using a primitive polynomial.
5. The base station of claim 1 , wherein the one more processors are configured to generate the binary sequence based on a maximum run length sequence (m-sequence) that is generated using a primitive polynomial.
6. The base station of claim 1 , wherein the one more processors are configured to insert a cyclic prefix prior to the SS OFDM symbols in the time domain.
7. The base station of claim 1 , wherein the one or more modulation schemes includes one or more binary phase shift keying (BPSK) or quaternary binary phase shift keying (QBPSK).
8. The base station of claim 1 , wherein N is a power of two integer.
9. The base station of claim 1 , wherein the binary sequence has a length of 63, 127 or 255 samples.
10. The base station of claim 1 , wherein the binary sequence has an extended length of 64, 128 or 256 samples.
11. A method to encode synchronization signals for transmission to a user equipment (UE), the method comprising:
generating a binary sequence;
modulating the binary sequence using one or more modulation schemes to form a modulated binary sequence;
performing one of an extension or truncation operation on the modulated binary sequence to obtain a modulated binary sequence that is equal to a discrete Fourier transform (DFT) length of N, wherein N is an integer;
performing a multiplication operation to the modulated binary sequence, wherein the multiplication operation involves multiplying the modulated binary sequence with an alternating sequence of {+1, +j} that is mapped to even or odd subcarriers in the frequency domain;
performing a DFT operation to map the modulated binary sequence equal of DFT length N to N subcarriers in a frequency domain;
performing an inverse DFT operation to the modulated binary sequence equal to DFT length N that is mapped to the N subcarriers in the frequency domain to obtain synchronization signal (SS) orthogonal frequency division multiplexing (OFDM) symbols in a time domain; and
encoding the SS OFDM symbols for transmission to the UE.
12. The method of claim 11 , further comprising transmitting the SS OFDM symbols to the UE.
13. The method of claim 11 , wherein the SS OFDM symbols form a primary synchronization signal.
14. The method of claim 11 , further comprising generating the binary sequence based on an m-sequence that is generated using a primitive polynomial.
15. The method of claim 11 , further comprising generating the binary sequence based on a maximum run length sequence (m-sequence) that is generated using a primitive polynomial.
16. The method of claim 11 , further comprising inserting a cyclic prefix prior to the SS OFDM symbols in the time domain.
17. The method of claim 11 , wherein the one or more modulation schemes includes one or more binary phase shift keying (BPSK) or quaternary binary phase shift keying (QBPSK).
18. The method of claim 11 , wherein N is a power of two integer.