Patent ID: 9077414
Filing Date: 2015-07-07
Classification: H04B,H04L

Abstract:
1. An apparatus comprising: a grouper configured to group antennas into antenna groups, if more antennas suitable for transmission are provided than pilot resources per a time slot within a frame structure, wherein the time slot comprises symbols for at least control data and pilot resources; a rotator configured to rotate selected symbols with at least one of antenna-specific, antenna group-specific, and data symbol-specific phases; a transmitter configured to transmit signals to at least a receiver, wherein the transmitting signals comprises transmitting symbols using a first antenna or first antenna group of a user device and transmitting the rotated symbols using at least one second antenna or second antenna group of the user device, wherein time-slot specific channel estimates are made for the received signals; and a multiplier configured to multiply, between time slots, half of the antennas within one of the antenna groups with a predetermined rotator.