Terminal devices, infrastructure equipment and methods
A terminal device for use with a wireless telecommunications system, the terminal device comprising: a transmitter; a receiver configured to receive a measurement radio signal from each of one or more potential relay nodes of the wireless telecommunications system, each measurement radio signal being transmitted using the same predetermined radio frequency band and identifying the one of the potential relay nodes from which it is transmitted; and a controller configured: to measure a characteristic of each received measurement radio signal, and based on each received measurement radio signal and its measured characteristic, to determine a suitable one of the one or more potential relay nodes for acting as a relay node for relaying the further radio signal between the terminal device and the infrastructure equipment.
1. A terminal device for use with a wireless telecommunications system, the terminal device comprising:
a transmitter;
a receiver configured to receive a measurement radio signal from each of one or more potential relay nodes of the wireless telecommunications system, each measurement radio signal being transmitted using the same predetermined radio frequency band, and each measurement radio signal identifying the one of the potential relay nodes from which it is transmitted; and
a controller configured:
to measure a characteristic of each received measurement radio signal indicative of the suitability of the potential relay node associated with that measurement radio signal for acting as a relay node for relaying a further radio signal between the terminal device and infrastructure equipment of the wireless telecommunications system, and
based on each received measurement radio signal and its measured characteristic, to determine a suitable one of the one or more potential relay nodes for acting as a relay node for relaying the further radio signal between the terminal device and the infrastructure equipment, and to control one of the transmitter to transmit the further radio signal to the infrastructure equipment via the determined relay node and the receiver to receive the further radio signal from the infrastructure equipment via the determined relay node, wherein the predetermined radio frequency band is a predetermined narrowband with a bandwidth defined by that of a predetermined number of physical resource blocks (PRBs) adjacent to each other in the frequency domain, the predetermined narrowband being only for the transmission of one or more of: the measurement radio signals, discovery signals, and establishment of a connection between the terminal device and one of the potential relay nodes.
2. A terminal device according to claim 1 , wherein the receiver is configured to receive radio signals transmitted over a bandwidth no greater than that of the predetermined radio frequency band.
3. A terminal device according to claim 1 , wherein the measurement radio signals transmitted from the one or more potential relay nodes are each transmitted at a different respective time.
4. A terminal device for use as a relay node in a wireless telecommunications system, the terminal device comprising a transmitter configured to transmit a measurement radio signal to a further terminal device of the wireless telecommunications system configured to use the terminal device as a relay node for relaying a further radio signal between the further terminal device and infrastructure equipment of the wireless telecommunications system, wherein the transmitted measurement radio signal:
identifies the terminal device;
comprises a characteristic measurable by the further terminal device and indicative of the suitability of the terminal device for acting as a relay node for relaying a further radio signal between the further terminal device and the infrastructure equipment; and
is transmitted using the same predetermined radio frequency band as usable for transmission of a measurement radio signal by one or more further potential relay nodes of the wireless telecommunications system, each of these measurement radio signals identifying the one of the one or more further potential relay nodes from which it is transmitted, and each of these measurement radio signals comprising a characteristic measurable by the further terminal device and indicative of the suitability of the one or more further potential relay nodes from which it is transmitted for acting as a relay node for relaying a further radio signal between the further terminal device and the infrastructure equipment, wherein the predetermined radio frequency band is a predetermined narrowband with a bandwidth defined by that of a predetermined number of physical resource blocks (PRBs) adjacent to each other in the frequency domain, the predetermined narrowband being only for the transmission of one or more of: the measurement radio signals, discovery signals, and establishment of a connection between the terminal device and one of the potential relay nodes.
5. A terminal device according to claim 4 , wherein the further terminal device is configured to receive radio signals transmitted over a bandwidth no greater than that of the predetermined radio frequency band.
6. A terminal device according to claim 5 , the terminal device comprising a receiver, wherein the transmitter is configured to transmit the further radio signal to the further terminal device and the receiver is configured to receive the further radio signal from the further terminal device using a radio frequency band associated with the terminal device, each of the terminal device and one or more further potential relay nodes being associated with a respective radio frequency band for transmission of the further radio signal.
7. A terminal device according to claim 6 , wherein the transmitter is configured to transmit a further measurement radio signal to the further terminal device, the transmitted further measurement radio signal being transmitted using the radio frequency band associated with the terminal device and comprising a characteristic measurable by the further terminal device and indicative of the suitability of the terminal device for acting as a relay node for relaying a further radio signal between the further terminal device and the infrastructure equipment.
8. A terminal device according to claim 7 , wherein the transmitter is configured to transmit the further measurement radio signal more frequently at a first time at which a strength or quality of radio signals transmitted by the infrastructure equipment is lower and less frequently at a second time at which the strength or quality of radio signals transmitted by the infrastructure equipment is higher.
9. Infrastructure equipment for use with a wireless telecommunications system comprising a first terminal device and one or more second terminal devices, the first terminal device being configured to receive a measurement radio signal from each of the one or more second terminal devices, each measurement radio signal being transmitted using the same predetermined radio frequency band, and each measurement radio signal identifying the one of the second terminal devices from which it is transmitted, to measure a characteristic of each received measurement radio signal indicative of the suitability of the second terminal device associated with that measurement radio signal for acting as a relay node for relaying a further radio signal between the first terminal device and the infrastructure equipment, and, based on each received measurement radio signal and its measured characteristic, to determine a suitable one of the one or more second terminal devices for acting as a relay node for relaying the further radio signal between the first terminal device and the infrastructure equipment, and to one of transmit the further radio signal to the infrastructure equipment via the determined second terminal device and receive the further radio signal from the infrastructure equipment via the determined second terminal device, the infrastructure equipment comprising a transmitter configured to transmit a radio signal to the first terminal device comprising information indicative of the predetermined radio frequency band, wherein the predetermined radio frequency band is a predetermined narrowband with a bandwidth defined by that of a predetermined number of physical resource blocks (PRBs) adjacent to each other in the frequency domain, the predetermined narrowband being only for the transmission of one or more of: the measurement radio signals, discovery signals, and establishment of a connection between the terminal device and one of the potential relay nodes.
10. Circuitry for a terminal device for use as a relay node in a wireless telecommunications system, the circuitry comprising transmitter circuitry, receiver circuitry and controller circuitry, wherein the controller circuitry is configured to control the transmitter circuitry to transmit a measurement radio signal to a further terminal device of the wireless telecommunications system configured to use the terminal device as a relay node for relaying a further radio signal between the further terminal device and infrastructure equipment of the wireless telecommunications system, wherein the transmitted measurement radio signal:
identifies the terminal device;
comprises a characteristic measurable by the further terminal device and indicative of the suitability of the terminal device for acting as a relay node for relaying a further radio signal between the further terminal device and the infrastructure equipment; and
is transmitted using the same predetermined radio frequency band as usable for transmission of a measurement radio signal by one or more further potential relay nodes of the wireless telecommunications system, each of these measurement radio signals identifying the one of the one or more further potential relay nodes from which it is transmitted, and each of these measurement radio signals comprising a characteristic measurable by the further terminal device and indicative of the suitability of the one of the one or more further potential relay nodes from which it is transmitted for acting as a relay node for relaying a further radio signal between the further terminal device and the infrastructure equipment, wherein the predetermined radio frequency band is a predetermined narrowband with a bandwidth defined by that of a predetermined number of physical resource blocks (PRBs) adjacent to each other in the frequency domain, the predetermined narrowband being only for the transmission of one or more of: the measurement radio signals, discovery signals, and establishment of a connection between the terminal device and one of the potential relay nodes.