Patent ID: 8503402

Claim:
A transmit unit for transmitting radio communication signals in a High Speed Downlink Packet Access, HSDPA, system, the transmit unit comprising: at least a first power amplifier coupled to a first antenna and a second power amplifier coupled to a second antenna for transmitting signals relating to a plurality of radio channels; first transmitting means configured to: transmit from both the first and second antennas using multi-antenna transmission, signals relating to a Dedicated Physical Channel, DPCH, using a first subset of channelization codes; transmit from both the first and second antennas using multi-antenna transmission, pilot signals on a first type of pilot channel for use as a reference for the DPCH using said first subset of channelization codes; and transmit from only the first antenna using single antenna transmission, signals relating to a High Speed Downlink Shared Channel, HS-DSCH, using a second subset of said channelization codes; and second transmitting means configured to: transmit only from the second antenna using single antenna transmission, signals relating to another channel that benefits from single antenna transmission; and balance a power load on the first and second power amplifiers by transmitting only from the second antenna using single antenna transmission, pilot signals on a second type of pilot channel, different from said first type of pilot channel, for use as a reference for the other channel and the HS-DSCH using said second subset of channelization codes; wherein the first subset of channelization codes together with the second subset of channelization codes covers the totality of the channelization codes of the HSDSCH, and wherein the first and second type of pilot channels are substantially covering the same area.