Methods and systems for CSI-RS resource allocation in LTE-advance systems

A method of allocating resource elements in an orthogonal frequency division multiplexed (OFDM) system for transmission of a channel state information reference signal (CSI-RS), comprising:

• converting one or more resource elements to a two-dimensional frequency-time domain;
• partitioning the one or more converted resource elements to units of a physical resource block (PRB);
• and
• patterning one or more resource elements over at least a portion of the PRB for transmission of the CSI-RS,
• wherein the CSI-RS resource elements per cell are patterned within the PRB as pairs of CSI-RS resource elements located within the same two ODFM symbols at every third pair of subcarriers counting downward from the pair of CSI-RS resource elements with a largest subcarrier index on the two OFDM symbols in one PRB, and wherein the same two OFDM symbols where pairs of CSI-RS resource elements can be allocated are symbol 9 and symbol 10, resulting in a reuse factor equal to 3.

A station configured to allocate resource elements in an orthogonal frequency division multiplexed (OFDM) system for transmission of a channel state information reference signal (CSI-RS), comprising:

• a converting unit configured to convert one or more resource elements to a two-dimensional frequency-time domain;
• a partitioning unit configured to partition the one or more converted resource elements to units of a physical resource block (PRB);
• and
• a patterning unit configured to pattern one or more resource elements over at least a portion of the PRB for transmission of the CSI-RS,
• wherein the CSI-RS resource elements per cell are patterned within the PRB as pairs of CSI-RS resource elements located within the same two OFDM symbols and at the first, sixth and seventh pair of subcarriers counting downward from the pair of CSI-RS resource elements with a largest subcarrier index on the two OFDM symbols in one PRB.

A station configured to allocate resource elements in an orthogonal frequency division multiplexed (OFDM) system for transmission of a channel state information reference signal (CSI-RS), comprising:

• a converting unit configured to convert one or more resource elements to a two-dimensional frequency-time domain;
• a partitioning unit configured to partition the one or more converted resource elements to units of a physical resource block (PRB);
• and
• a patterning unit configured to pattern one or more resource elements over at least a portion of the PRB for transmission of the CSI-RS,
• wherein the CSI-RS resource elements per cell are patterned within the PRB as pairs of CSI-RS resource elements located within the same two ODFM symbols at every third pair of subcarriers counting downward from the pair of CSI-RS resource elements with a largest subcarrier index on the two OFDM symbols in one PRB, and wherein the same two OFDM symbols where pairs of CSI-RS resource elements can be allocated are symbol 9 and symbol 10, resulting in a reuse factor equal to 3.

A non-transitory computer-readable medium storing instructions thereon to perform a method of allocating resource elements in an orthogonal frequency division multiplexed (OFDM) system for transmission of a channel state information reference signal (CSI-RS), the method comprising:

• converting one or more resource elements to a two-dimensional frequency-time domain;
• partitioning the one or more converted resource elements to units of a physical resource block (PRB);
• and
• patterning one or more resource elements over at least a portion of the PRB for transmission of the CSI-RS,
• wherein the CSI-RS resource elements per cell are patterned within the PRB as pairs of CSI-RS resource elements located within the same two OFDM symbols and at the first, sixth and seventh pair of subcarriers counting downward from the pair of CSI-RS resource elements with a largest subcarrier index on the two OFDM symbols in one PRB.

A non-transitory computer-readable medium storing instructions thereon to perform a method of allocating resource elements in an orthogonal frequency division multiplexed (OFDM) system for transmission of a channel state information reference signal (CSI-RS), the method comprising:

• converting one or more resource elements to a two-dimensional frequency-time domain;
• partitioning the one or more converted resource elements to units of a physical resource block (PRB);
• and
• patterning one or more resource elements over at least a portion of the PRB for transmission of the CSI-RS,
• wherein the CSI-RS resource elements per cell are patterned within the PRB as pairs of CSI-RS resource elements located within the same two ODFM symbols at every third pair of subcarriers counting downward from the pair of CSI-RS resource elements with a largest subcarrier index on the two OFDM symbols in one PRB and wherein the same two OFDM symbols where pairs of CSI-RS resource elements can be allocated are symbol 9 and symbol 10, resulting in a reuse factor equal to 3.