Correction of Estimated SIR Used for Transmit Power Control

A device configured to estimate a signal-to-interference-ratio (SIR) as basis for transmit power control of a radio signal transmitted from a transmitter to a receiver over a radio channel, the device comprising:

• an obtaining element configured to obtain a channel estimate (h) of the radio channel and to obtain a combining weight (w);
• and
• a calculating element operatively coupled to the obtaining element and configured to generate an estimated SIR value based on the channel estimate (h) and the combining weight (w) such that the estimated SIR value equals a first estimated SIR value multiplied by a numerical factor, the numerical factor being dependent on the channel estimate (h) and the combining weight (w) such that the numerical factor attains a minimum value whenever the channel estimate (h) and the combining weight (w) are linearly dependent.

A base station for a radio access network, the base station comprising a device configured to estimate a signal-to-interference-ratio (SIR) as a basis for transmit power control of a radio signal transmitted from the base station to a receiver over a radio channel, the device comprising:

• an obtaining element configured to obtain a channel estimate (h) of the radio channel and to obtain a combining weight (w);
• and
• a calculating element operatively coupled to the obtaining element and configured to generate an estimated SIR value based on the channel estimate (h) and the combining weight (w) such that the estimated SIR value equals a first estimated SIR value multiplied by a numerical factor, the numerical factor being dependent on the channel estimate (h) and the combining weight (w) such that the numerical factor attains a minimum value whenever the channel estimate (h) and the combining weight (w) are linearly dependent.