Multi transmit antenna synchronization channel transmission cell ID detection

A method for multi-transmit (TX) antenna synchronization channel transmission cell identification (ID) comprising the steps of:

• performing, by a user equipment (UE) a cell search to find a predetermined timing and primary synchronization channel (P-SCH) sequence;
• detecting a number of TX antennas used for receiving a synchronization channel (SCH) and primary broadcast control channel (P-BCH);
• determining, by a control unit, the number of transmit (TX) antennas used;
• if the number of TX antennas detected is 1, then conventionally performing a correlation to the received RSs;
• if the number of TX antennas detected is more than 1, then:
• determining reference symbol (RS) groups by applying orthogonal codes to the RSs and summing the RSs to determine the group RS;
• correlating the N group RS to the orthogonal cell ID codes;
• determining the cell ID code maximizing correlation power;
• and,
• reading the P-BCH.

An apparatus for multi-transmit antenna synchronization channel transmission cell identification (ID), comprising:

• a front end receiver (Fe RX) adapted to receive a signal from an antenna;
• an analog filter adapted to filter a signal bandwidth (BW) coupled to an output of the Fe RX;
• an analog to digital converter (ADC) coupled to the output of the analog filter and adapted to convert an analog signal to a digital signal;
• a first digital filter adapted to receive and digitally filter the digital signal from the ADC;
• a Fast Fourier transform (FFT) unit adapted to receive the digital signal filtered by the first digital filter;
• a second, smaller, digital filter adapted to receive the digital signal from the ADC and adapted to filter out the synchronization channel (SCH) BW;
• a cell search unit adapted to receive the digital signal filtered by the second, smaller, digital filter, the cell search unit adapted to perform primary synchronization channel (P-SCH) and secondary synchronization channel (S-SCH) detection, wherein the detected S-SCH is used as a phase reference in a cell ID detection unit;
• a Fast Fourier Transform (FFT) unit adapted to receive timing information obtained in the P-SCH detection stage from the cell search unit;
• a control unit adapted to receive the detected number of TX antennas used for synchronization channel (SCH) and primary broadcast control channel (P-BCH) transmission from the cell search unit, said control unit adapted to perform reference symbol (RS) grouping;
• and
• a cell identification (ID) detection unit adapted to receive the information necessary to correlate phase equalized RS samples to orthogonal cell ID codes and output the cell ID.

A computer software program embodied on a non-transitory computer readable medium adapted to be executed by computer hardware, comprising program code adapted to:

• perform a cell search to find a predetermined timing and primary synchronization channel (P-SCH) sequence;
• detect a number of TX antennas used for receiving a synchronization channel (SCH) and primary broadcast control channel (P-BCH);
• determine the number of transmit (TX) antennas used;
• if the number of TX antennas detected is 1, then conventionally perform a correlation to the received reference symbols (RSs);
• if the number of TX antennas detected is more than 1, then:
• determine RS groups by applying orthogonal codes to the RSs and summing the RSs to determine the group RS;
• correlate the N group RS to the orthogonal cell ID codes;
• determine the cell ID code maximizing correlation power;
• and
• read the P-BCH.