HK1076568B - Method and system for optimizing power resources in wireless devices - Google Patents

Description

Method and system for optimizing power resources in a wireless device

Technical Field

The present invention relates generally to the field of wireless communications, and more particularly to optimizing power resources of wireless devices in a wireless communication system.

Background

Portable electronic devices often run out of battery and the data sent to the device is often short (e.g., EMAIL, instant messaging, digital updates, status changes). When devices seek transmissions addressed to them, the power consumed by the devices often exceeds the power required to receive such transmissions. Moreover, the devices typically only occasionally have transmissions addressed to them. Despite the fact that most devices only occasionally have transmissions addressed to them, the device must nevertheless maintain an attentive state throughout the notification. This means that many devices lose energy throughout the notification, even in the general absence of data to them.

It is desirable for devices to be able to quickly determine whether the data is intended for them and, if not, to go back to a power saving mode (sleep mode) to save energy.

Disclosure of Invention

The present invention relates to a method and system for optimizing power resources in a wireless device that utilizes a list of messages adapted so that the device can quickly determine whether the list contains messages to be transmitted to them, thereby reducing the amount of time the device must remain awake while searching for messages.

Drawings

Fig. 1 is a message list in which a count of the number of destination identifiers included in the message list is provided at the beginning of the message list and further wherein all of the destination identifiers are listed before all of the individual indicators in accordance with an embodiment of the present invention.

Fig. 2 is a message list in which a count of the number of destination identifiers included in the message list is provided at the beginning of the message list and further wherein each destination identifier and its associated indicator are listed together in increasing numerical order according to an embodiment of the present invention.

FIG. 3 is a flowchart showing method steps for a device to determine whether the message list shown in FIG. 1 or FIG. 2 includes any messages for the device for which the device is expected to have a message in the message list, in accordance with one embodiment of the present invention.

Fig. 4 is a flow chart showing method steps for a device to determine whether the message list shown in fig. 1 or fig. 2 includes any messages for the device for which the device is expected to have more than one message with the same identifier in the message list, in accordance with an embodiment of the present invention.

FIG. 5 is a flowchart of method steps for a display device to determine whether the message list shown in FIG. 1 or FIG. 2 includes any messages for the device for which it is expected that the device has more than one message with the same identifier or multiple identifiers in the message list, in accordance with one embodiment of the present invention.

Fig. 6 is a message listing in which a listing terminator is included at the end of the message and further in which each destination identifier and its associated indicator are listed together in increasing numerical order according to embodiments of the present invention.

FIG. 7 is a flowchart showing method steps of a display device to determine whether the message list shown in FIG. 6 includes any messages for the device, in accordance with one embodiment of the present invention.

Fig. 8 is a system for optimizing power resources in a wireless device in accordance with an embodiment of the present invention.

Detailed Description

Preferred embodiments of the present invention are described with reference to the figures of the accompanying drawings, wherein like numerals represent like elements.

Referring initially to fig. 1, a message list 10 is shown. The wireless device typically synchronizes with the network so that the device knows to wake up for a predetermined period and check for any messages for these devices. To conserve battery, the wireless device preferably not only sleeps between predetermined periods, but also takes as little time as possible to determine if there is a device's message. Wireless devices typically determine whether they are the intended recipient of a message by examining a list of messages. The prior art message list includes not only a number of identifiers showing the destination of each message contained in the list and a count of the number of messages in it, but also the message itself. Including the message itself in the message list increases the time that the wireless device must remain awake when deciding whether the message list has a message for the device. For example, when the message list includes 10 messages listed in ascending order of destination identification and there are messages sent to one to four devices, a wireless device with device identification "5" must remain awake not only for the first four message identifications, but also for the first four messages themselves, which will go back to sleep once device "5" receives its message until the next time the message list is received, which as mentioned occurs at predetermined intervals.

To reduce the time that devices must remain awake when determining whether the particular message list contains messages to be sent to them, the present invention provides for message lists as shown in fig. 1, 2 and 6. These message lists may be modified as desired/needed to maximize the message determination methodology without departing from the scope of the present invention.

Referring initially to fig. 1, a first embodiment of a message list 10 is shown in accordance with the present invention. The message list 10 includesA count of the number of destination identifiers contained in the message list is provided at the beginning of the message list 10. In this embodiment, the count is indicated by reference numeral 12 and is referred to as the "listed identification number count". The destination identification code is denoted by reference numeral 14_1-NListed in increasing numerical order. Each destination identification code_1-NWith associated message indicators. In this embodiment, the message indicator_1-NAre also listed in ascending numerical order and are designated generally by the reference numeral 16.

In an alternative embodiment, as shown in FIG. 2, the message list 10 may be configured such that the message indicator_1-N16 at their associated destination identifiers_1-N14 (c). Note that in FIGS. 1 and 2, the destination identifier is shown_1-N14 and their associated message indicators_1-N16 are organized in monotonically increasing numerical order, but may also be organized in monotonically decreasing numerical order.

A logic diagram showing the method 30 for determining whether a message has arrived for a wireless device, which may be any form of wireless device such as a wireless telephone, personal digital assistant, or pocket personal computer, is shown in fig. 3. The methods shown in figures 3, 4, and 5 can be applied to two embodiments of the message lists shown in figures 1 and 2.

The method 30 begins at step 32 by initializing the device's search pointer to the first identifier and loading the count of the listed identifiers into a count variable (i.e., the entry or memory location containing the count). The method 30 then proceeds to step 34 to determine whether the count equals zero. If the count is equal to zero, the method 30 proceeds to step 36, where the message flag is cleared. If the count is not equal to zero, the method proceeds to step 38, where the destination identifier pointed to by the pointer search is loaded by the device at method 38. The device preferably loads the destination identifier into the processing component of the device, and once the destination identifier is loaded by the device, method 30 proceeds to step 40, where the destination identifier is compared to the device identifier to determine whether the destination identifier is greater than the device identifier. If so, there is no subsequent message for the device and the method 30 proceeds to step 36 where the message flag is cleared, as described above. If not, the method 30 proceeds to step 42, where it is determined whether the destination identifier is equal to the device identifier. If the destination identification is equal to the device identification, then there is a message for the device and the method 30 proceeds to step 44. At step 44, the message flag is set and an indicator to the message corresponding to the destination identification is loaded, and if the destination identification is not equal to the device identification, then method 30 proceeds from step 42 to step 46. At step 46 the search indicator is advanced to the next destination identification and at step 48 the count is decremented.

Referring now to fig. 4, a method 50 of determining whether a message has arrived at the wireless device is shown. In this embodiment, the device is expected to have more than one message with the same device identification within the message list. The method 50 begins with step 52 in which a search indicator of the wireless device is initiated to a first identifier, a count of the listed identifiers is loaded into a count variable, and the listed messages and message flags are cleared. From step 52, the method proceeds to step 54, where it is determined whether the listed identifier count is equal to zero, if the count is equal to zero, the method 50 ends at step 56, if the count is not equal to zero, the method 50 proceeds to step 58, where the destination identifier pointed to by the search indicator is loaded by the wireless device. From step 58, the method proceeds to step 60 where it is determined whether the destination identifier is greater than the device identifier. If the destination identification is greater than the device identification, the method 50 proceeds to step 56, where the method ends, as described above. If the destination identification is not greater than the device identification, the method 50 proceeds to step 62, where it is determined whether the destination identification is equal to the device identification.

If the destination identifier is equal to the device identifier, step 62, the message flag is set and an indicator to the message corresponding to the destination identifier is added to the message list for the particular wireless device performing method 50 (step 64). From step 64, the method proceeds to step 66, where the search indicator is advanced to the next destination identification, and if at step 62 the destination identification does not equal the device identification, then method 50 proceeds directly from step 62 to step 66. After step 66, the count of the listed identification code is decremented by an amount that may be determined as desired.

Referring now to fig. 5, a method 70 of determining whether a message has arrived at the wireless device is shown. In this embodiment, the device is expected to have more than one message with the same device identification or multiple identifications within the message list. Multiple device identifiers for a single device may be used, for example, where a user of a particular device registers for several wireless multicast services. By way of illustration, a device may have a message identification code that is specific to the device and which has another identification code that accompanies a set of devices. In this way, the entire group can send only a single identification code and a message. A device may also seek transmissions that are propagated to an arbitrary number of devices, such as sports game data and stock reports.

The method 70 begins with step 72 in which a search indicator to the first device identification is initiated, the listed identification count is loaded into a count variable, the flag and listed message are cleared, and the first test identification from the list of test messages is loaded into the processing component of the wireless device. The test message list contains all the identifiers for which the device is receptive during the time that the window is awake to check for message acceptance. The test list should be a monotonic order suitable for searching for the received identification code. From step 72, the method 70 proceeds to step 74, where it is determined whether the listed identifier count is equal to zero, if so, the method 70 ends at step 76, otherwise, the method 70 proceeds to step 78, where the destination identifier pointed to by the search indicator is loaded into the processing component of the device. Proceed to step 80 where it is determined whether the destination identifier is greater than the test identifier. If so, the method proceeds to step 82 where it is determined whether there is another test identifier in the test list, if so, the next test identifier is loaded at step 84 and the method returns to step 74, if there is no other test identifier, the method 70 ends at step 86.

Returning to step 80, if the destination identifier is not greater than the test identifier, the method 70 proceeds to step 88 where it is determined whether the destination identifier is equal to the test identifier at step 88. If so, then a message flag is set and an indicator to the message corresponding to the destination identification is added to the message list (step 90). From step 90, the method 70 proceeds to step 92. If, on the other hand, the destination identification is not equal to the test identification, the method 70 proceeds directly to step 92. The search indicator is advanced to the next destination identification at step 92 and the count of the listed identification is decremented at step 94, the amount of count decrements being determined as desired.

Referring now to fig. 6, another embodiment of a message manifest 100 is shown in accordance with the present invention in which a count of identifiers is not listed, but rather a manifest terminator 102 is listed, wherein the message manifest is terminated by a unique number at the location of a generic identifier. In the incremental identifier embodiment, the valid value of the terminator is zero. In this way, only the indicator must be changed during the search, and a comparison of identifiers greater than the identifiers in the list ends the search.

A method by which a device can determine whether the message list shown in fig. 6 includes messages for any of these devices is shown in fig. 7. The method 120 begins at step 122 by initializing a search pointer to a first destination identifier, at step 124, the destination identifier pointed to by the search pointer is loaded into the processing component of the device, and at step 126, it is determined whether the destination identifier is equal to the end value (i.e., the value of the list terminator). If the destination identification is equal to the end value, the method proceeds to step 128 where the message flag is cleared and the method 120 ends. If the destination identifier is not equal to the end value, the method 120 proceeds to step 130 where it is determined whether the destination identifier is greater than the device identifier of the particular device, i.e., whether the message list includes messages for that device. If the destination identification is greater than the device identification, the method 120 proceeds to step 128 where the message flag is cleared and the method 120 ends. If the destination identifier is less than or equal to the device identifier, the method 120 proceeds to step 132.

At step 132, it is determined whether the destination identifier is equal to the device identifier. If so, the message flag is set and an indicator to the message corresponding to the destination identifier is loaded to the processing component of the device (step 134), if not, the search indicator is advanced to the next destination identifier at step 136 and the method 120 continues at step 124.

The previous form is used or some variations of the form presented are based on the efficiency of the values that accompany the identifier and message indicator, and the processing device, to search for messages. The indicator to the message may be a simple programming language indicator to the data defining the existence of the actual message transmission, or it may be the data itself. The actual data may be in the form: carrier channel, broadcast time period, and channel decoding. If the message data is very short (e.g., a telephone number), it is often more efficient to insert the message into the normal position of the message pointer. In this case, one or more bits of the message indicator portion of the data stream must be reserved as defining bits for the other bits present. For example, two bits may be encoded such that one encoding shows the remaining bits as the message, followed by an encoding to an indicator of the message, and a third encoding as an indicator to the data defining where to find the subsequent message, a fourth encoding possibility being a backup for some future use.

With regard to the implementation of the invention in 3G radio access networks, there are two basic methods of identifying "destination" and "message indicator", either the broadcast (BCCH on BCH/P CCPCH) or dedicated (DCCH on DCH/DPCCH + DPDCH) signal. If a dedicated signal is applied, the signal is specific to the "destination" and there is no application or benefit to permute the control data order since all signals are for the destination device. If the broadcast signal is applied, the existing mechanism for recovering the data is not relevant to the processing of the data.

The embodiments described above are generally the fastest way to place or decide on a device-less message when the number of messages is small. However, when the list is long, a fast method may be used to search for a list of monotonically increasing or decreasing messages. For example, a binary calculus protocol requires log on average₂(counting) test. These calculations are more complex and different processors may perform these calculations at different speeds. Generally, if there are more than about 32 received identifiers, the binary algorithm is faster for a single identifier under test. If many identification codes are tested, the sequential test is more effective for counting a large number of codes. The selection of the protocol may also be selected based on the identification code or the value of the identification code being tested. If the single number to be searched is low and the received sequence (i.e., message list) monotonically increasing, the best approach is to start the search at the beginning of the received data. If the signal number is high and the received sequence monotonically increases, the best approach is to start the search at the end of the received data. (data is often transmitted in sectors in a wireless system and is paged for error correction reasons, so all sector data must be received and decoded before any data can be checked.) a preferred embodiment of the present invention is a number distribution of the sought identification codes that takes into account the number of received identifications, whether one or more identifications are sought, and the choice of the search protocol used for each search event.

Referring now to fig. 8, a system 200 is shown for optimizing power resources in a wireless device. The system 200 includes at least one Radio Network Controller (RNC), at least one Base Station (BS), and at least one wireless device (206). The wireless device 206 includes a processor 208 to search for messages in a message list, wherein the device 206 is the intended recipient. To maximize the amount of time that the device 206 is asleep (i.e., clock-only, which informs the device to periodically wake up), the message list is employed as described above. The device 206 determines whether a particular message list includes the device's messages based on the form of the message list using the methods described above.

Although specific processing functions have been described as being performed by specific components, it should be appreciated that the performance of processing functions may be distributed among system components as desired.

Although the present invention has been described in detail, it is to be understood that the invention is not limited thereto and that various changes may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims (5)

1. A method of receiving a message at a wireless device, comprising:

synchronizing with a wireless network to enable the wireless device to wake up from a power saving mode within a predetermined time interval to receive a message list;

receiving the message list, the message list having no message data and including a destination identifier and a message indicator associated with the destination identifier, wherein the destination identifier indicates a device for which the message is intended, and wherein the destination identifier is included in the message list prior to the associated message indicator;

detecting that the destination identification code corresponds to the wireless device; and

in response to detecting that the destination identification code corresponds to the wireless device, the wireless device processes the message indicator and receives the message indicated by the message indicator.

2. The method of claim 1, wherein the message list further includes a count of the destination identifiers in the message list.

3. The method of claim 1 wherein the message list further comprises a list terminator.

4. The method of claim 1, further comprising reverting to a power-saving mode when the message list does not include the destination identifier corresponding to the wireless device.

5. An apparatus for receiving a message at a wireless device, the apparatus comprising:

means for synchronizing with a wireless network to cause the wireless device to wake up from a power save mode within a predetermined time interval to receive a message list;

means for receiving the message list, the message list having no message data and comprising a destination identification and a message indicator associated with the destination identification, wherein the destination identification indicates a device for which the message is intended, and wherein the destination identification is included in the message list prior to the associated message indicator;

means for detecting that the destination identification code corresponds to the wireless device; and

means for processing the message indicator and receiving a message indicated by the message indicator in response to detecting that the destination identification code corresponds to the wireless device.