US Patent 9439158 Efficient extended power headroom reporting for semi-persistent scheduling

The invention relates to a method for transmitting power headroom information from a user equipment to the base station. The transmission is made dependent on scheduling type of the uplink resource, for which the power headroom information is to be calculated and over which it is to be transmitted. If the uplink resource is dynamically scheduled, then the extended power headroom report according to Rel. 10 is transmitted; if it is scheduled persistently, e.g. as part of a semi-persistent scheduling configuration, then a basic power headroom report according to Rel. 8/9 is transmitted. The invention circumvents the problem of delaying data in persistently allocated uplink resources when transmitting an extended power headroom report.