The present invention relates to telecommunications, and more particularly to a method of wireless communication.
In known networks for mobile telecommunications, the time intervals between a mobile user terminal “waking up” so as to start to listen to a paging channel are of constant length.
In an embodiment of the present invention, a method of intermittent activation of receiving circuitry of a mobile user terminal is provided to listen to a paging channel. The activation may be periodic. The period may be selected dependent upon either the time of day or which of a plurality of types of service may be provided in the last call connection to the mobile user terminal. Another example is a corresponding network for mobile telecommunications.
Some embodiments of the present invention may have the period, also known as discontinuous reception cycle length, adjusted dependent upon the type of service required. The period may be shorter where, for example, the call connection is in respect of a service requiring a fast response, such as an ‘interactive' service, as compared to where the call connection is in respect of a service needing only a slow response, such as a ‘background’ service. This has the advantage that a mobile user terminal that requires a ‘background’ service, avoids wasting precious battery power by listening to the paging channel more often than it needs to.
Some embodiments may have another period, in particular a Core Network (“CN”) discontinuous reception cycle length, which may be set dependent upon on the time of day. The time of day may be a guide to expected traffic activity. For example, users may be more likely to receive calls during the daytime rather than in the early hours of the morning, so the period may be selected to be shorter in the daytime. This leads to more efficient use of the energy in the mobile user terminal's battery since the mobile user terminal may not wake up so often to listen to the paging channel if the likelihood of an incoming call is relatively low.
The present invention will be better understood from reading the following description of non-limiting embodiments, with reference to the attached drawings, wherein below:
It should be emphasized that the drawings of the instant application are not to scale but are merely schematic representations, and thus are not intended to portray the specific dimensions of the invention, which may be determined by skilled artisans through examination of the disclosure herein.
One wireless communications network is a Universal Mobile Telecommunications System (“UMTS”) terrestrial access network (“UTRAN”), which is a type of wideband code division multiple access (“CDMA”) network for mobile telecommunications. An exemplary UTRAN network is shown in
Discontinuous Reception (Discontinuous Reception) to Save Battery Power
When a mobile user terminal is not actively sending or receiving data (e.g., not in a call connection), it may listen for any call connection requests coming in on a paging channel. As shown in
As shown in
It will be understood that the longer the discontinuous reception cycle length, the longer time it is likely to take to establish the call. However, in this case the battery life of the mobile user terminal before a recharge is required is extended. On the other hand, if a shorter discontinuous reception cycle length is used, the time taken to establish the call may be reduced, but the battery life may be shortened as a consequence.
In the UMTS network 2, two discontinuous reception cycles are defined namely at UTRAN level and at core network level. These are considered in turn below.
Setting UTRAN Discontinuous Reception Cycle Length
The UTRAN discontinuous reception cycle length may be selected to be different for different mobile user terminals and its value may be signalled to the mobile user terminal by the UMTS network 2 whenever a control-signalling connection to the mobile user terminal exists. This discontinuous reception cycle may be applied if the mobile user terminal has a signalling connection to the UMTS network 2, but may not be actively sending or receiving user data, in other words the mobile user terminal is in UTRAN Registration Area—Paging Channel mode (which is often denoted URA_PCH mode).
As shown in
As shown in
The information of UTRAN discontinuous reception cycle length may be transmitted to the particular mobile user terminal as part of the dedicated control-signalling involved in setting up the call to that mobile user terminal. Once the call has finished, the mobile user terminal thereafter uses the selected UTRAN discontinuous reception cycle length it has been informed of, at least until a new call to the mobile user terminal in respect of a different type of service may cause a fresh UTRAN discontinuous reception cycle length to be selected.
Setting the UTRAN discontinuous reception cycle length depending on service type may saves energy in the mobile user terminal's battery whilst providing an appropriate response time for the most likely next expected service.
The UTRAN discontinuous reception cycle length may be set as part of a packet switched call. As shown in
UTRAN DRX cycle length may be selected dependent upon the type of service, for example as shown in Table 1.
In some other embodiments, UTRAN discontinuous reception cycle length for a mobile user terminal may be selected dependent not only on service type to that mobile user terminal but also other service parameters. One example is quality of service (“QoS”) class, where certain classes of mobiles get higher priority. Another example may be proximity to a base station.
Setting CN Discontinuous Reception Cycle Length
The core network (“CN”) domain discontinuous reception cycle length is generally longer than that of the UTRAN discontinuous reception cycle length. The CN discontinuous reception cycle length may be used by the mobile user terminal when the mobile user terminal is in idle mode. That is when it does not have any call connections to the UMTS network 2 (and is, of course, a different mode to URA_PCH mode). All the mobile user terminals in the UMTS network 2 are informed about the discontinuous reception cycle length through the system information broadcast (SIB) which may be a regular broadcast to all mobile user terminals.
As shown in
During the busiest call activity period (e.g., 4 pm to 6 pm), the CN discontinuous reception cycle length may be set to a shorter value still (e.g., 100 milliseconds).
As shown in
Setting the CN discontinuous reception cycle length depending on the time of day makes efficient use of the mobile user terminal battery life. This may be because the mobile user terminal effectively wakes up less frequently when it is less likely to receive an incoming call.
While the particular invention has been described with reference to illustrative embodiments, this description is not meant to be construed in a limiting sense. It is understood that although the present invention has been described, various modifications of the illustrative embodiments, as well as additional embodiments of the invention, will be apparent to one of ordinary skill in the art upon reference to this description without departing from the spirit of the invention, as recited in the claims appended hereto. Consequently, processing circuitry required to implement and use the described system may be implemented in application specific integrated circuits, software-driven processing circuitry, firmware, programmable logic devices, hardware, discrete components or arrangements of the above components as would be understood by one of ordinary skill in the art with the benefit of this disclosure. Those skilled in the art will readily recognize that these and various other modifications, arrangements and methods can be made to the present invention without strictly following the exemplary applications illustrated and described herein and without departing from the spirit and scope of the present invention. It is therefore contemplated that the appended claims will cover any such modifications or embodiments as fall within the true scope of the invention.