Method and apparatus for transmitting reference signal

A method for receiving signals by a communication apparatus in a wireless communication system, the method comprising:

• receiving, by the communication apparatus, a plurality of reference signals in one or more resource blocks on respective antenna ports of a first and second set of antenna ports,
• wherein each reference signal received on the first set of antenna ports is code division de-multiplexed from a first group of resource elements in the one or more resource blocks by using a corresponding orthogonal sequence,
• wherein each reference signal received on the second set of antenna ports is code division de-multiplexed from a second group of resource elements in the one or more resource blocks by using a corresponding orthogonal sequence, and
• wherein the first set of antenna ports comprises antenna ports {N, N+1, N+4, N+6} and the second set of antenna ports comprises antenna ports {N+2, N+3, N+5, N+7}.

A communication apparatus for transmitting signals in a wireless communication system, the communication apparatus comprising:

• a radio frequency (RF) unit;
• and
• a processor operatively connected to the RF unit and configured to:
• map a plurality of reference signals to one or more resource blocks, and
• transmit the mapped plurality of reference signals on respective antenna ports of a first and second set of antenna ports,
• wherein each reference signal transmitted on the first set of antenna ports is code division multiplexed to a first group of resource elements in the one or more resource blocks by using a corresponding orthogonal sequence,
• wherein each reference signal transmitted on the second set of antenna ports is code division multiplexed to a second group of resource elements in the one or more resource blocks by using a corresponding orthogonal sequence, and
• wherein the first set of antenna ports comprises antenna ports {N, N+1, N+4, N+6} and the second set of antenna ports comprises antenna ports {N+2, N+3, N+5, N+7}.

A communication apparatus for receiving signals in a wireless communication system, the apparatus comprising:

• a radio frequency (RF) unit;
• and
• a processor operatively connected to the RF unit and configured to:
• receive a plurality of reference signals in one or more resource blocks on respective antenna ports of a first and second set of antenna ports,
• wherein each reference signal received on the first set of antenna ports is code division de-multiplexed from a first group of resource elements in the one or more resource blocks by using a corresponding orthogonal sequence,
• wherein each reference signal received on the second set of antenna ports is code division de-multiplexed from a second group of resource elements in the one or more resource blocks by using a corresponding orthogonal sequence, and
• wherein the first set of antenna ports comprises antenna ports {N, N+1, N+4, N+6} and the second set of antenna ports comprises antenna ports {N+2, N+3, N+5, N+7}.