GB2371447A

GB2371447A - Battery power conservation for radio communication equipment

Info

Publication number: GB2371447A
Application number: GB0101289A
Authority: GB
Inventors: Peter Chambers
Original assignee: Roke Manor Research Ltd
Current assignee: Roke Manor Research Ltd
Priority date: 2001-01-18
Filing date: 2001-01-18
Publication date: 2002-07-24
Also published as: GB0101289D0

Abstract

User equipment used in a radio communication network monitors local traffic and accordingly changes the state of the user equipment. The user equipment operates in either a discontinuous or continuous mode of operation. The continuous mode of operation is entered when required by the detected local traffic. The method may further include switching to the discontinuous mode of operation when this is permitted by the detected local traffic.

Description

A Radio Communication Method And Apparatus This invention relates to a radio communication method and apparatus particularly, but not exclusively, for mobile communication.

It is known in present, and it is proposed for communication systems such as 3GPP (third generation partnership project), to undertake measures to reduce the power consumption of equipment.

Power consumption is an important factor for user equipment design. A battery provided for such equipment must have a useful capacity whilst being as compact as possible to give an overall size for the equipment which is acceptable to the user. It is the battery size which makes the most significant contribution to the overall size.

One approach to reducing the drain on the battery and hence to increase the time before battery replacement or re-charging is required, is to operate the equipment in a discontinuous mode. In such a mode, a transmitter section of the user equipment is only active for short periods when required. Discontinuous operation may apply to both data and control streams. Such a mode is desirable when packetised data is used as the communication medium, for example, when the user is browsing over the Internet.

It has been previously proposed for 3GPP that the signalling for control of the mode or"state"of the user equipment be a high level signalling in which the system communicates via the base-station.

The current invention arose from an inventive realisation that another technique would confer significant technical advantages.

According to the invention there is provided a radio communication method comprising the steps of at an user equipment monitoring local traffic and switching from a first state, in which the user equipment operates in a discontinuous mode, to a second state, in which the user equipment operates in a continuous mode, upon detection of local traffic requiring a continuous mode operation.

By the user equipment monitoring local traffic and switching from a first state to a second state applicable to the mode required by the local traffic, the requirement for signalling might be eliminated or at least reduced. It should be appreciated that the user equipment could also be responsive to signalling traffic from the system in order to switch modes in addition to acting in the autominous manner set out above. By local traffic it is meant that generated locally by the user equipment or equipment connected to the user equipment rather than traffic received by the user equipment over the radio communications network. In a sense the user equipment is the first network node for such local traffic.

A second aspect of the invention provides apparatus.

A specific embodiment of the invention will now be described, by way of example only, with reference to the drawings in which:

Figure 1 shows a radio communications system in schematic form ; Figure 2 shows user equipment used in the system shown in Figure 1; Figure 3 is a base-station present in the system shown in Figure 1; Figure 4 shows communication channels; Figure 5 is an explanatory figure illustrating a CDMA multiple access scheme; Figure 6 shows the user equipment of figure 2 in terms of functionality; and Figure 7 shows in schematic form a method in accordance with the invention.

With reference to figure 1, a communications system 1 comprises a number of base sites 2 to 7, a number of radio transceivers hereinafter referred to as user equipment (UE) two of which, labelled 8 and 9, are shown. The system is a 3generation Partnership Project (3GPP) system and the base stations are sometimes referred to as NodeB. They

are considered to be the access points to the network since they serve geographically displaced cells enabling UE within the cell to establish communication links via radio channels 10. The cellular nature of the network with its attendant features of call establishment, hand-over and the like will be well known to a person skilled in the art.

One of the NodeBs, labelled 7, in the figure is connected to the other base sites via communication links 11 to 15. A further communication link 16 links this network to other networks 17. NodeB 7 includes a network controller for the network 1 in addition to being a base-site for a particular cell.

The user equipment 8 and 9 are of nominally similar design. As is shown in Figure 2, the user equipment comprises a microprocessor 18, memory 19, a display 20, a keypad 21, a transmitter section 22, a receiver section 23, an antenna switch 24, an antenna 25 and a battery 26. A microphone 28 permits the input of speech to the microprocessor which processes it in the usual manner familiar to a person skilled in the art into a digital form. A speaker 27 enables received sound to be output after it has been decoded by the microprocessor 18.

The microprocessor 18 provides the"intelligence"for the user equipment by running a program held in the memory 19 and it is connected to all the aforementioned components by a data and a control bus. It provides the control, signal processing, and other functionality such as browsing of the Internet.

The battery 26 provides the power required for the user equipment.

The keypad 21 is an input device that enables a user of the equipment to enter numbers to be called and other input commands for example, commands to activate browsing of the Internet.

The transmitting section 22 includes the radio frequency circuitry for generating the required RF output of the user equipment from digital data passed to it by the microprocessor 18. The receiver section 23 includes the radio frequency for demodulating a received radio signal and providing a demodulated signal output to the microprocessor 18.

The microprocessor 18 then further processes the received signal in a manner familiar to the person skilled in the art.

An antenna switch 24 is controlled by the microprocessor 24 to selectively connect the receiver section 23 or the transmitter section 22 to the antenna 25. The antenna 25 is externally mounted on the user equipment such that it is uppermost when the equipment is in use to facilitate good reception and transmission properties.

The base-stations will also have a configuration familiar to a person skilled in the art and will also be only briefly described. As is shown in Figure 3, a base station 4 comprises a controller 29, a memory 30, a transmitter and receiver section 31, an antenna 32 connected to the transmitter and receiver section 31, a network connection 33 and input and output devices 34. The controller 29 is microprocessor based and controls all the elements of the base station 4 and also inter-operates with the network controller 7.

The system is configured to provide a dedicated signalling channel 35 having an uplink and a downlink, and a set of data channels 36 again having an uplink and downlink. By downlink it is meant that information flows from the particular base station to the user equipment and uplink means that information flows up from the user equipment to the base-site. The signalling channel comprises control information such as that used in handover when a user moves between cells and other control information, for example, power level control. The data channel 36 carries data destined for use by a user for example speech from a user of the user equipment 8 is placed on the uplink of the traffic channel 36. It is then received by the base-station and passed on via the network to another user. Similarly, voice is passed from the base station to the user equipment via the data downlink.

It should be appreciated that by channels it can mean communication links carried by particular frequencies in so called frequency division multiple access (FDMA) or time slots in a time division multiple access (TDMA) structure or in the case of code division multiple access differently coded data. In this specific embodiment, the system is a Code Division Multiple Access CDMA system in which the channels are defined by codes. Users operate at the same time and on the same frequencies but with different codes using spread spectrum techniques

to provide the channels as shown in figure 5.

As mentioned before, the microprocessor 18 is programmed to offer various functionality. One of the functions may be the provision of an Internet browsing capability using a suitable wireless access protocol. In this way the user equipment enables the user to connect via the network 1 to the Internet. Thus, the user equipment can be configured in terms of functionality as shown in Figure 6 to provide a browser capability 37 linked to a communications capability 38 and hence via a radio link to a network 1 and onwards to the internet.

The browser 37 is selected for use by the user selecting a menu driven set of options by key input at the keypad 21 and this causes local traffic 39 indicated on the link between the browser 37 and the communications capability 38. A local traffic monitor 40 monitors for local traffic 39 generated by the browser 37 and provides an output which is passed to a state switch 41. The state switch 41 then changes the state of the communications capability 38 such that the user equipment operates in continuous transmission mode to the base-station 4. After the user has finished with Internet activities the local traffic 39 ceases and the state switch changes the communications capability to a state in which the user equipment operates in discontinuous mode in order to conserve battery life.

The method is further illustrated in Figure 7. In a first step 42, the local traffic 39 is monitored. In a second step 43, the state

appropriate to the detected load traffic is determined. The determined rp appropriate state is then compared with the actual state in step 44. If the states are in agreement then the microprocessor 18 returns to the monitoring step 42. If there is not agreement, then the state is changed, step 45, and the processor returns to the monitoring step, step 42.

Claims

1 A radio communication method comprising the steps of at an user equipment monitoring local traffic and switching from a first state, in which the user equipment operates in a discontinuous mode, to a second state, in which the user equipment operates in a continuous mode, upon detection of local traffic requiring a continuous mode operation.

2 A method as claimed in claim 1 in which the user equipment is switched from the second state to the first state when the detected local traffic is determined by the user equipment as permitting discontinuous mode operation.

3 A radio communication method substantially as hereinbefore described with reference to and or as illustrated by the drawings.

4 Apparatus for radio communication operable in at least a respective first and a respective second state in which the apparatus operates in a discontinuous communication mode and a continuous communication mode respectively comprising a monitor for monitoring local traffic to provide a monitored output and a state switch responsive to the monitored output to switch the apparatus state such that when the monitored traffic permits the use of a discontinuous mode the first state is maintained or

4 Apparatus for radio communication operable in at least a respective first and a respective second state in which the apparatus operates in a discontinuous mode and a continuous mode respectively comprising a monitor for monitoring local traffic to provide a monitored output and a state switch responsive to the monitored output to switch the apparatus state such that when the monitored traffic permits the use of a discontinuous mode the first state is maintained or

entered or when the monitored traffic requires the use of a continuous mode the second state is maintained or entered.

5 Apparatus for radio communication substantially as hereinbefore described with reference to and or as illustrated by the drawings.

Amended claims have been filed as follows Claims

1 A radio communication method comprising the steps of at a user equipment monitoring local traffic and switching from a first state, in which the user equipment operates in a discontinuous communication mode, to a second state, in which the user equipment operates in a continuous communication mode, upon detection of local traffic requiring a continuous mode operation.