User terminal, base station and radio communication method

Patent metadata

Field	Value
Publication number	US-10154479-B2
Application number	US-201414910318-A
Country	US
Kind code	B2
Filing date	Jul 18, 2014
Priority date	Aug 8, 2013
Publication date	Dec 11, 2018
Grant date	Dec 11, 2018

Abstract

The present invention is designed to adequately control small cells (small base stations) on/off in a structure where small cells and macro cells are arranged to overlap each other. A user terminal can communicate with a macro base station that forms a macro cell and a small base station that forms a small cell arranged within the macro cell, and has a measurement section that measures the received power of a detection/measurement signal that is transmitted from the small base station in a predetermined subframe, and the total received power of downlink signals in a subframe in which no detection/measurement signal is transmitted, a calculation section that calculates received quality by using the received power and the total received power, and a transmission section that transmits information related to the received quality to the macro base station, the calculation section calculates the received quality based on the proportion of the received power and the value given by adding the received power to the total received power.

First claim

The invention claimed is:

1. A user terminal comprising:
a receiver that receives a detection/measurement signal transmitted from a given cell;
a processor that measures received power (RSRP: Reference Signal Received Power) of the detection/measurement signal and total received power (RSSI: Reference Signal Strength Indicator) of a downlink signal in a subframe in which the detection/measurement signal is transmitted; and
a transmitter that transmits information about a measurement result,
wherein when the detection/measurement signal is transmitted using a part of symbols in the subframe, the processor measures the RSSI from all OFDM (Orthogonal Frequency Division Multiplexed) symbols of the downlink signal of the subframe in which the detection/measurement signal is transmitted,
wherein the receiver receives information, comprising a measurement timing configuration, about the detection/measurement signal, and
wherein the measurement result is based, at least in part, on the information.

2. A base station comprising:
a transmitter that transmits, in a given cell, a detection/measurement signal to a user terminal by using a part of symbols of a subframe; and
a receiver that receives information about a measurement result of received power (RSRP: Reference Signal Received Power) of the detection/measurement signal measured by the user terminal and total received power (RSSI: Reference Signal Strength Indicator) measured from all OFDM (Orthogonal Frequency Division Multiplexed) symbols of a downlink signal of the subframe in which the detection/measurement signal is transmitted,
wherein the transmitter further transmits information, comprising a measurement timing configuration, about the detection/measurement signal, and
wherein the measurement result is based, at least in part, on the information.

3. A radio communication method for a user terminal, comprising:
receiving a detection/measurement signal transmitted from a given cell;
measuring received power (RSRP: Reference Signal Received Power) of the detection/measurement signal and total received power (RSSI: Reference Signal Strength Indicator) of a downlink signal of a subframe in which the detection/measurement signal is transmitted; and
transmitting information about a measurement result,
wherein when the detection/measurement signal is transmitted using a part of symbols in the subframe, the user terminal measures the RSSI from all OFDM (Orthogonal Frequency Division Multiplexed) symbols of the downlink signal of the subframe in which the detection/measurement signal is transmitted,
wherein the method further comprises: receiving information, comprising a measurement timing configuration, about the detection/measurement signal, and
wherein the measurement result is based, at least in part, on the information.

Assignees

• Ntt Docomo Inc

Inventors

• Takeda Kazuaki
• Harada Hiroki
• Ishii Hiroyuki

Classifications

• H04W72/21

  in the uplink direction of a wireless link, i.e. towards the network · CPC title

• H04W72/23 Primary

  in the downlink direction of a wireless link, i.e. towards a terminal · CPC title

• H04B17/328

  Reference signal received power [RSRP]; Reference signal received quality [RSRQ] · CPC title

• H04W72/042 Primary

  Electricity · mapped topic

• H04W52/0206

  in access points, e.g. base stations · CPC title