Channel State Information Feedback

A method comprising:

• a) receiving, by a wireless device, a first reference signal from a first base station on a first plurality of OFDM resources in a first subframe in a plurality of subframes, said first plurality of OFDM resources depending at least in part on a first base station identifier of said first base station;
• b) estimating, by said wireless device, a first signal strength corresponding to said first base station based on said received first reference signal;
• c) receiving, by said wireless device, a second reference signal from a second base station, on a second plurality of OFDM resources in said first subframe, said second plurality of OFDM resources depending at least in part on a second base station identifier of said second base station;
• d) estimating, by said wireless device, a second signal strength corresponding to said second base station based on said received second reference signal;
• e) estimating, by said wireless device, an interference value on said second plurality of OFDM resources based at least in part on said second reference signal;
• and
• f) calculating, by said wireless device, a signal to interference ratio value based on said second signal strength and a total interference value, wherein:
• i) if said first plurality of OFDM resources do not overlap with said second plurality of OFDM resources, said total interference value is computed based upon said interference value;
• and
• ii) if said first plurality of OFDM resources overlap with said second plurality of OFDM resources, said total interference value is computed based upon said interference value minus said first signal strength.

A wireless device comprising:

• a) one or more communication interfaces;
• b) one or more processors;
• and
• c) memory storing instructions that, when executed, cause the wireless device to:
• i) receive a first reference signal from a first base station on a first plurality of OFDM resources in a first subframe in a plurality of subframes, said first plurality of OFDM resources depending at least in part on a first base station identifier of said first base station;
• ii) estimate a first signal strength corresponding to said first base station based on said received first reference signal;
• iii) receive a second reference signal from a second base station, on a second plurality of OFDM resources in said first subframe, said second plurality of OFDM resources depending at least in part on a second base station identifier of said second base station;
• iv) estimate a second signal strength corresponding to said second base station based on said received second reference signal;
• v) estimate an interference value on said second plurality of OFDM resources based at least in part on said second reference signal;
• and
• vi) calculate a signal to interference ratio value based on said second signal strength and a total interference value, wherein:
• (1) if said first plurality of OFDM resources overlap with said second plurality of OFDM resources, said total interference value is computed based upon said interference value;
• and
• (2) if said first plurality of OFDM resources do not overlap with said second plurality of OFDM resources, said total interference value is computed based upon said interference value plus said first signal strength.