Pilot channel configuration for MIMO network

A radio network controller, in a wireless communication network, for configuring additional pilot channels in a cell having primary and secondary pilot channels to support multiple-input, multiple-output (MIMO) transmissions of rank three or higher, the radio network controller comprising:

• a network interface circuit for communicating with a serving base station in a cell managed by the radio network controller;
• and
• a control processor for controlling the radio base station, said control processor being configured to:
• send a configuration message to a serving base station in a cell having one or more pilot channels configured, said configuration message including configuration information for one or more additional pilot channels;
• determine a set of two or more power levels for the additional pilot channels;
• include, in the configuration information, power information indicating the set of two or more power levels for each additional pilot channel;
• send a measurement initiation request to the base station to configure reporting, by the base station, of the power levels of the additional pilot channels, said measurement initiation request indicating a type of reporting selected from a plurality of types of reporting performed by the base station.

A method, implemented by a serving base station for a cell of a wireless communication network, for supporting multiple-input, multiple-output (MIMO) transmissions of rank three or higher, the method comprising:

• transmitting primary and secondary pilot channels on a downlink channel;
• receiving, from a radio network controller, a configuration message including configuration information for one or more additional pilot channels, the configuration message including power level information indicating a set of two or more power levels for each additional pilot channel;
• selecting, for each additional pilot channel, a transmit power level from a corresponding set of two or more power levels indicated in the configuration information;
• transmitting the additional pilot channels on the downlink channel at the selected power levels
• receiving a measurement initiation request from the radio network controller, said measurement initiation request indicating a type of reporting selected from a plurality of types of reporting performed by the base station;
• and
• configuring, responsive to the measurement initiation request, measurement reporting to report the power levels of the additional pilot channels to the radio network controller.

A serving base station for a cell of a wireless communication network for supporting multiple-input, multiple-output (MIMO) transmissions of rank three or higher, the serving base station comprising:

• a transceiver circuit for communicating with user terminals;
• a network interface circuit for communicating with a radio network controller in the wireless communication network;
• and
• a control processor connected to the transceiver circuit and network interface circuit and configured to:
• control the transceiver circuit to transmit primary and secondary pilot channels on a downlink channel;
• receive, from a radio network controller, a configuration message including configuration information for one or more additional pilot channels, the configuration message including power level information indicating a set of two or more power levels for each additional pilot channel;
• select, for each additional pilot channel, a transmit power level from a corresponding set of two or more power levels indicated in the configuration information;
• control the transceiver circuit to transmit the additional pilot channels on the downlink channel at the selected power levels
• receive a measurement initiation request from the radio network controller, said measurement initiation request indicating a type of reporting selected from a plurality of types of reporting performed by the base station;
• and
• configure, responsive to the measurement initiation request, measurement reporting to report the power levels of the additional pilot channels to the radio network controller.