KR100954763B1 - Reduction of power consumption in wireless communication terminals - Google Patents

Abstract

The present invention relates to a mechanism for reducing power consumption in a wireless terminal intended for a communication system in which the availability of common public media is determined by the terminal prior to transmission. The terminal selects at least one communication device as a communication peer, the signal strength received from at least one of the at least one wireless communication device and optional other parameters measured from at least one of the at least one wireless communication device. Adjust receiver performance based on the receiver performance, wherein the receiver performance is adjusted to receive the at least one wireless communication device having a reduced power consumption. The terminal generates an indication when the terminal's transmission is approaching and readjusts receiver performance to determine the availability of common public media at a performance level capable of detecting devices interrupted by the terminal's transmission.

Power consumption, wireless communication

Description

Reduction of power consumption in wireless communication terminals

The present invention generally relates to a reduction in power consumption in wireless communication terminals. More particularly, the present invention relates to a mechanism for reducing power consumption through receiver performance control in wireless terminals.

Current developments towards mobile computing and networking have led to the evolution of several access technologies that provide users with Internet access when they are outside their home network. Currently, wireless Internet connections are typically based on either or both of short range wireless systems or mobile networks.

Near field wireless systems have a typical range of one hundred meters or less. They often combine with wired systems over the Internet to provide communication over long distances. The category of short-range wireless systems includes wireless personal area networks (PANs) and wireless local area networks (WLANs). They have a common feature of operating in the unlicensed portions of the radio spectrum, usually in the 2.4 GHz industrial, scientific, medical (ISM) or unlicensed bands of 5 GHz.

Wireless personal area networks use low cost, low power wireless devices having a typical range of about 10 meters. The best known example of wireless personal area network technology is Bluetooth using the 2.4 GHz ISM band. It provides a maximum air link speed of 1Mbps and power consumption small enough for personal use, portable electronics such as PDAs and mobile phones. WLANs generally operate at higher peak rates from 10 Mbps to 100 Mbps, have longer ranges, and require greater power consumption.

Wireless LAN systems are typically an extension of a wired network that provides mobile users with a wireless connection to a wired network. Examples of WLAN technology are IEEE 802.11 a, which is designed for an unlicensed band of 5 GHz and uses Orthogonal Frequency Division Multiplexing (OFDM) to deliver at 54 Mbps data rate, and 11 Mbps data rate, designed for the 2.4 GHz ISM band. It includes the HIPERLAN standard, which is designed to operate in 802.11b and 5GHz unlicensed bands using direct sequence spread spectrum (DSSS).

In wireless LAN technology, two basic network topologies, ad-hoc network and infrastructure network, are available for network configuration. The ad hoc network is formed by two or more independent mobile terminals communicating on a peer-to-peer basis without the service of the base station, ie in the ad hoc network. Ad hoc networks are usually formed for temporary purposes. Next, the infrastructure network includes one or more wireless infrastructure stations called access points that form a wired infrastructure. In a typical network of this type, regardless of whether the traffic is between two terminals or between the terminal and the wired network, all traffic passes through the access point, ie mobile terminals do not communicate on a common layer communication basis. Do not. Mobile terminals are provided with wireless LAN cards, where they can connect to a wired network or set up an ad hoc network. In an infrastructure network, an access point and at least one terminal are described as forming a Basic Serving Set (BSS), while an ad hoc network is also called an independent BSS (IBSS).

Up to now, wireless LAN technology has typically been used in laptop computers, which are typically AC power, but can also be used in battery mode, which provides significant high battery capacity. To extend the life of batteries, WLAN standards define specific power saving modes that terminals can enter from active mode to reduce their power consumption. In this mode, WLAN specific power consumption is very low, but terminals wake up periodically (ie, enter active mode) to receive beacon transmission broadcasts. Indication transmissions indicate, for example, whether there are incoming packets buffered for the terminal. If so, the terminal retrieves the packets, goes back to sleep, and wakes up again to receive the next indication transmission.

Current WLAN power management has been designed assuming laptop type computers in which terminal devices are characterized by relatively high battery capacity. With the generalization of several other types of personal communications devices such as intelligent phones with smaller size and less battery capacity than laptop computers, however, power consumption is important when new features are designed for wireless systems and terminals. It has been an issue. Recent ad hoc mode applications, which may be more power hungry, exacerbate the problem. Examples of such applications may be games playing in small groups or business meetings in which a large number of files may be shared by participants.

The power consumption of WLAN terminals is typically reduced by trying to maximize the time they spend in power saving mode. However, this does not affect power consumption in active mode, and its ratio to the total time, ie the percentage of time in active mode, is increasing with the generalization of new functionalities.

The present invention relates to a communication system such as a WLAN provided in an uncoordinated media access mechanism, i.e., a system in which terminals must sense common public media before transmission to know if the media is free, so that the terminal's power consumption is the active mode of the terminal. To achieve a solution that can be reduced.

The present invention seeks to invent a new mechanism for reducing the power consumption of a wireless terminal operating in a wireless communication system in which a common channel is received before transmission to determine if the channel is free.

In the present invention, the terminals select the device (s) with which it is to communicate and in two different control modes, namely the reception control mode for receiving the selected device (s) and the media for sensing common public media before transmission of the terminals. Controls the performance of its receiver in access control mode.

Performance control is performed in a manner that allows for performance degradation to reduce power consumption. More suitable methods for controlling the performance of the receiver include controlling the dynamic range and / or sensitivity of the receiver. The dynamic range here refers to the input power range where the receiver produces useful outputs. Sensitivity then refers generally to the receiver's ability to sense (weak) signals, i.e. degraded sensitivity reduces the area in which devices can be detected. The concept of dynamic range includes the concept of sensitivity because the low end of the dynamic range is controlled by sensitivity. The performance of the receiver can be particularly degraded in the receive control mode, and the next degradation can be implemented to allow for reduced power consumption at the receiver.

Thus, the terminal selects the device (s) to communicate at each time. In an ad hoc network, the selected device (s) typically form a subset of all possible communication peers in the same network. The terminal measures signal quality variables from at least one of the selected device (s), each signal quality variable indicating a characteristic of a signal received from each device. The quality variable typically indicates the strength of the received signal. If there is no transmission required for the selected device (s), the performance of the receiver of the terminal may be adjusted based on the signal quality variable (s) obtained based only on the device (s). Thus, if no transmission is required, the terminal may limit the operating range of its receiver in accordance with the signal (s) received from the device (s). This allows the terminal to be received with degraded performance, i.e. received with reduced power consumption, but it also causes devices outside this area to be hidden nodes, i.e., undetectable nodes. When a transmission comes in, the terminal readjusts the performance of its receiver to detect the traffic of all those devices that the incoming transmission can interfere with when sensing the common media. In this way, you can see that the terminal has not exacerbated the hidden node problem.

Thus, one embodiment of the present invention is to provide a method for reducing power consumption in a wireless communication terminal. The method includes selecting at least one device as a communication peer in a wireless communication system and measuring a signal quality variable from at least one of the at least one communication device selected in the selection step, each signal quality variable being selected Measured based on a signal received from each one of the at least one communication device selected in step, wherein at least one quality variable is obtained. The method includes adjusting receiver performance based on at least one of the at least one signal quality variable obtained in the measuring step, wherein the adjusting step is performed while acknowledging receipt of each signal from the at least one communication device selected in the selecting step. Monitoring the transmission of a wireless communication terminal coming to reduce consumption, and the availability of common public media at a performance level capable of detecting transmission of communication devices within the service area of the transmission of the wireless communication terminal; And reconditioning receiver performance to determine that the reconditioning step is performed when the monitoring step indicates that a transmission of the wireless communication terminal is coming.

In another embodiment, the present invention provides a wireless terminal for a wireless communication system in which terminals are required to determine availability of common media prior to transmission. The wireless terminal comprises selection means for selecting at least one communication device as a communication peer in a communication system and first measuring means for measuring a signal quality variable from at least one of the at least one communication device, each signal quality variable Are measured based on signals received from each one of the at least one communication device, where at least one signal quality variable is obtained. The wireless terminal comprises first performance control means for re-adjusting receiver performance based on at least one of the at least one signal quality variable such that the wireless communication terminal receives respective signals from the at least one communication device with reduced power consumption; Second performance control means for adjusting the receiver performance to a level of performance that allows the terminals to detect transmission of communication devices within the service area of the transmission of the wireless terminal, wherein the second performance control means comprises: It is configured to operate when the transmission of the terminal indicates an upcoming.

In a further embodiment, the present invention provides a computer usable media having computer readable program code implemented to control a wireless communication terminal. The computer readable program code is based on a portion of the first computer readable program code for causing the at least one communication device to be selected as a communication peer of the wireless communication terminal and the signal received from the wireless communication terminal at least one of the at least one wireless communication device. And a second computer readable program code portion for adjusting receiver performance based on the measured signal quality variable. The computer readable program code includes a third computer readable program code portion for causing the wireless communication terminal to generate an indication when a transmission is approaching and causing the wireless communication terminal to detect transmission of communication devices within the service area of the transmission of the wireless communication terminal. And further comprising a fourth computer readable program portion for adjusting receiver performance to a level such that the fourth computer readable program code portion operates in response to the indication.

In a typical case, a terminal has only one or at most several communication peers in close proximity to it, and the performance of the receiver is significantly lower during the reception period. This, in turn, translates into significant power savings. Moreover, the performance of the receiver can be degraded without worsening the known hidden node problem, which can cause simultaneous transmissions (collisions) and can reduce throughput.

Other features and advantages of the present invention will become apparent with reference to the following detailed description and the accompanying drawings.

In the following, the invention and its many embodiments have been described in more detail with reference to the examples shown in FIGS. 1 to 8 with the accompanying drawings, in which:

1 illustrates an exemplary communication system in accordance with the present invention;

2 illustrates a MAC entity used in an IEEE 802.11 network;

3 is a flow chart showing one embodiment of the control mechanism of the present invention;

4 is a flow chart showing another embodiment of the control mechanism of the present invention;

5 is a block diagram illustrating one embodiment of a control mechanism of the present invention in a terminal;

6 is a flow diagram illustrating one embodiment of a control mechanism for canceling the performance of a receiver in a receive control mode;

7 is a flowchart of a further embodiment of the present invention; And

Figure 8 shows one embodiment of a terminal according to the invention.

1 illustrates a typical WLAN communication system. The system includes one or more WLAN networks 100, each connected by a gateway 101 (router) with another network, such as the Internet, including service providers 102. Each WLAN network includes one or more access points 103, each of which communicates wirelessly with a terminal within a coverage area, ie a cell, thus forming a bridge between the terminals and the wired network.

As described above, it has been described above that an access point and at least one terminal in an infrastructure network form a Basic Service Set (BSS). The series of BSSs then forms an Extended Service Set (ESS). These BSSs are connected to each other by a distribution system (DS), which can be a wired network, such as an internal Ethernet LAN, over which TCP / IP packets are transmitted, or a wireless network, or a combination of both. However, the base type of IEEE 802.11 LAN is a standalone BSS (IBSS) consisting of two or more terminals. The terminals of the IBSS form an ad-hoc network 110.

Terminals of the present invention are typical short-range wireless communications that may be based, for example, on IEEE 802.11 standards for wireless local area networking. The terminals may be portable computers, PDA devices, intelligent telephones or other such mobile terminals 120. In the same way as a typical GSM telephone, user-operated terminals may consist of two parts: an actual subscriber device and an identification module, in which the subscriber device only functions as a terminal when the identification module is inserted into it. do. The identification module can be, for example, a (universal) Subscriber Identity Module (U) SIM, a User Identity Module (UIM) or a (User) integrated circuit card (User). Integrated Circuit Card ((U) ICC)). However, the terminals can be quite equivalent to traditional WLAN terminals that do not use identification modules.

The system may typically further include an authentication server 130 of the WLAN. The authentication server is connected to the gateway described above via a secure connection, which is a typical TCP / IP connection established over an operator network or the Internet. As shown in the figure, access points broadcast an indication message 30 in an infrastructure network, while terminals share this obligation in an ad hoc network.

Since the present invention is not related to the structure of the WLAN system, it is not described in more detail here.

In the communication system as shown in Fig. 1, terminals must detect the media before they can transmit, in order to confirm that the media is idle. For this purpose, IEEE 802.11 standards use Carrier Sense Multiple Access / Collision Avoidance (CSMA / CA), media access control (MAC) to avoid simultaneous transmission (i.e., collision). Include a protocol. A common problem associated with such an environment is a hidden node problem that occurs when two nodes can communicate with a third node but cannot communicate with each other due to long distances, obstructions and the like. For example, a terminal may connect to the media because it may not be able to hear an access point or other terminal currently communicating with a third terminal. In the present invention, power consumption is reduced through deterioration of receiver performance without exacerbating hidden node problems.

The IEEE 802.11 standard defines physical layer options and MAC layer protocols for wireless LANs. 2 illustrates a protocol structure of the IEEE 802.11 standard. As shown in the figure, the actual MAC protocol operates within the lower sublayer of the second layer of the OSI layer model, which is the data link layer (DLL). The MAC management layer is responsible for the overall management of the MAC layer. For example, it supports combining and roaming functions, and controls the synchronization of terminals with power saving functions, authentication and encryption mechanisms. The MAC management layer further maintains a MAC layer management database, that is, a management information base (MIB) of the MAC layer. The MAC layer cooperates with the physical management layer to maintain the database. An example of a MAC layer attribute that may be used in the performance control mechanism of the present invention is a Received Signal Strength Indicator (RSSI) indicating the level of a received signal. Alternatively, the received signal strength can be defined internally when the physical layer is executed and can be used for the control mechanism of the present invention without any connection with MAC protocols.

The physical layer is divided into two sublayers, a Physical Layer Convergence Protocol (PLCP) sublayer and a Physical Medium Dependent (PMD) sublayer. The purpose of the PLCP is to provide a minimum dependency on the PMD to simplify the interface between the physical and MAC layers.

As mentioned above, the performance of a receiver can be controlled by controlling its sensitivity or dynamic range. Since these methods require somewhat different measurements at the terminals, they are described individually below.

3 is a flow diagram illustrating one embodiment of a performance control mechanism at a wireless communication terminal. In an embodiment, performance control may be performed by controlling the sensitivity of the receiver. When terminals operate in a network, such as a WLAN network, that competes for common air media, the terminal first selects one or more devices that need to communicate, and establishes a communication link with each of the devices to establish a dedicated communication group by itself. (Step 30). In an infrastructure network only neighboring access points are selected, whereas in an ad hoc network a terminal may select one or more other terminals. The selection can be carried out in a number of ways depending on the system involved. For example, the terminal autonomously detects devices in the same network and presents a list of detected devices to the users, so that the user can select the appropriate device (s) to communicate with. The terminal also allows the method of the present invention to begin autonomously. It may include a preliminary storage list of devices in proximity of it.

The terminal then establishes a minimum signal to noise ratio for each of the selected devices, ie for each link (step 31). This is done depending on the link parameters used, such as the data rate received. If the link parameters used are unknown, then the minimum signal-to-noise ratio is assumed assuming the worst case, i.e. the largest possible signal-to-noise ratio requirement. Moreover, a performance or safety margin is set for each minimum value to ensure reliable transmission on the link.

The terminal then determines whether it has entered the receive control mode or the media access control mode. The decision is made based on whether the terminal needs to transmit soon (step 32).

If the terminal can remain in receive mode without transmitting, the strength of the received signal is measured for each received link. The measured signal strength represents the average level of signal input from the link to the receiver of the terminal (step 33).

Based on the minimum signal to noise ratio, the associated performance limits, and the measured signal strength, the terminal individually estimates the maximum allowable total interference for each link. The ratio of measured signal strength to the maximum allowable total interference corresponds to a signal to noise ratio that exceeds the minimum signal to noise ratio by the performance limit. Total interference here refers to receiver-originated interference, which includes noise and other unwanted components generated by the receiver.

Based on the estimate, the sensitivity of the receiver can be lowered to reduce the receiving power required at the terminal (step 35). That is, by lowering the sensitivity of the receiver, the power consumption of the receiver is reduced to a small value in consideration of the desired signal-to-noise ratio. If the selected devices are received simultaneously, the sensitivity value is determined by the link with the tightest sensitivity requirement, i.e. the link with the smallest maximum amount of total interference allowed. However, if the terminal can receive each selected device in the dedicated time zone, then the sensitivity value for the time zone is determined by the link, and the sensitivity changes to the new link characteristic value when the received link changes. In this respect, the operation depends on the network.

Since local area networks are quite stable in short time periods, it is possible to degrade the sensitivity of the receiver based on the received signal strength value (s) measured from the device (s) for which communication is required. If there are two or more such devices, the interference level requirement is set individually for each device (link). However, the number of sensitivity levels used during the reception period depends on how many and which of the selected devices should be received at the same time.

In the manner described above, the terminal limits the operating range of its receiver corresponding to the area covered by the selected devices, and the devices outside the area may be hidden nodes. However, since the terminal has only received so far, this does not harm the operation of the system.

When the transmission of the terminal is imminent, an indication of the transmission request is generated and provided to the process of the present invention. As a result, the terminal enters a media access control mode to cause all such devices to be "exposed", which can be interrupted by upcoming transmissions (step 32 / yes). For example, an indication may be obtained from the transmit buffers when the transmitter begins to assemble a packet or frame to be transmitted. In the media access control mode, receiver sensitivity is adjusted to detect all nodes where a collision may occur in the upcoming transmission phase, ie the terminal "exposures" all such nodes. In one embodiment, receiver sensitivity is adjusted to a maximum (step 36) to minimize the risk of hidden nodes. Channel occupancy is then detected, and media is connected according to the media access protocol used in the system (step 37). In IEEE 802.11 networks, for example, carrier sense multiple access / collision avoidance (CSMA / CA) media access protocol is used to share a common channel.

The transmit power can be adjusted according to the link. When the transmission is successfully completed, the process regresses to adjust the receiver sensitivity to the receive mode (steps 33 to 35).

In another embodiment of the invention, the sensitivity of the receiver is not adjusted to the maximum value in step 36, but to a smaller value depending on the link. Depending on the link parameters, the terminals first determine a sufficient transmit power value for the link. A propagation path loss model can be used to estimate the areas where upcoming transmissions may interfere with other devices. The sensitivity of the receiver can then be adjusted to a level sufficient to detect all nodes in the area, i.e., cells in which upcoming transmissions may cause interference.

The sensitivity control described above allows several very small cells to be formed, which do not interfere with each other and do not interfere with the operation of the access point. For example, several laptop / headset pairs can operate simultaneously without disturbing each other.

The group of communication devices can be updated during the operation of the terminal. For example, the terminal may receive an indication that either of the selected devices has entered or entered sleep mode. If the link is one that determines the sensitivity of the receiver, the sensitivity is varied depending on the needs of the selected residual devices. Moreover, new devices can be joined to the network and the terminal can select one or more of them as its communication group.

As mentioned above, the power consumption of the transceiver can also be reduced by controlling the dynamic range of the receiver. 4 is a flow diagram illustrating one embodiment of a control mechanism for controlling the dynamic range of a receiver. 4 corresponds to that of FIG. 3, but in the two control modes described above, the terminal controls the dynamic range of the receiver. In the receive control mode, the terminal measures the received signal strength (step 43) received on each link as in step 33 described above. The terminal then measures the amount of interfering power indicative of the total amount of external interference received by the receiver (step 44). In an embodiment, interference from external obstructions is considered.

The measured interference power may indicate the total cutoff power, that is, the total power going into the active parts of the receiver, the intermodulation power, or the adjacent channel power. Based on the minimum signal to interference ratio determined in step 41, the associated performance limit, the measured signal strength, and the measured power value (s), the terminal determines the optimal operating point for performance and power consumption (step 45a). The operating point is set to an optimum value (step 45b). Operation point here generally refers to internal transceiver settings that yield the desired dynamic range and power consumption. As will be described below, for example, the setting can include supply voltage settings and / or bias current settings.

When the media access control mode is connected, the terminal adjusts the dynamic range of the receiver to a maximum value (step 46) or a value small enough to detect all (transmitting) nodes in the area where upcoming transmissions may cause interference. Adjust with In the case of sensitivity control, the transmission determined for the upcoming transmission can be used when setting the smaller value.

5 is a diagram illustrating one embodiment of performance control execution within a terminal. The measurement block 50 handles the measurement of the signal strength and supplies the measured value, such as RSSI, to the network control logic block 51 which calculates the maximum noise / interference allowed for the selected links. The network control logic may also receive other network parameters required by the control process, such as the data rate used within the network. The calculated data is fed to a receiver power control logic block 52 which determines internal control measurements that change the sensitivity or dynamic range of the receiver to achieve reduced power consumption. The receiver power control logic block then controls the components in the receiver signal path 54 to obtain the dynamic range associated with the desired sensitivity or the desired power consumption. The receiver power control logic block can also control the synthesizer 53 of the transceiver including power consumption components. An indication of the coming transmission may be given to a network control logic block that controls the receiver power control logic, for example to infer the media connection control mode. The receiver can also be divided into controllable blocks 56. Each of the blocks may be individually controlled as described below with respect to FIG.

The receiver power control logic block may be provided with one or more look-up tables that map the required change in sensitivity or dynamic range to the internal control mechanism used. It is also possible for the measured signal strength values to map directly to internal control mechanisms in the lookup table. Therefore, the measured signal strength value can also be provided directly to the receiver power control logic as indicated by dashed arrows in the figure. Thus, the internal control mechanism indicates the operating points described above.

The sensitivity or the dynamic range of the receiver can be controlled in various ways depending on the structure of the receiver. Different blocks in the receiver signal path can be controlled to achieve a dynamic level associated with a desired level of sensitivity or a desired power consumption. For example, the gain of a low-noise front-end amplifier (LNA) and / or the resolution of an analog-to-digital converter can be controlled. Circuit-level power save mechanisms used in the present invention have been described in US patent applications US2003 / 0124999 A1 and US2003 / 0078007 A1. In general, receiver power consumption can be reduced in many ways. For example, power consumption may vary by various bias currents or supply voltages in the receiver, by bypassing one or more receiver stages, by selecting signal paths with smaller / higher power consumption, and / or by reducing power consumption. It can be controlled by shutting down the excitation components. In particular, the control of bias currents and the selection of different signal paths are effective techniques to reduce power consumption. The measurements required for control can be either analog domain power detectors or digital measurement structures. They provide the information needed for the control logic to control the power consumption of the receiver blocks.

6 shows one embodiment of a control mechanism for controlling the performance of a receiver in a receive control mode. In an embodiment, the variable (s) measured based on the received packets are once used to determine the gain of the receiver chain (step 60), and other receiver performance requirements may be applied to the antenna port or RF input of the terminal. See step 61). As mentioned above, the measured variable (s) depends on whether the sensitivity or dynamic range is controlled. In both embodiments, the received signal strength is measured, and the interference power is additionally measured in the case of dynamic range control. The receiver is divided into several controllable blocks, and in step 62 the gain and the receiver's requirements are divided between different receiver blocks. Then, each receiver block can be controlled according to its requirements (step 63). Internal control information can be retrieved from one or more survey tables, for example. Each controllable block may include one or more low noise amplifiers, down-conversion mixers, base or IF amplifiers, analog to digital converters, local oscillator buffers, or voltage controlled oscillators. As mentioned above, the synthesizer of the transceiver may also be controlled to reduce power consumption.

The terminal then checks if the set performance level is sufficient, i.e., packets have been received correctly (step 64). If this is the case, the terminal waits for the next packets (step 66) and repeats the steps, i.e. measures the variables and controls different receiver blocks according to their needs. If performance is insufficient, the terminal increases the performance limit (step 65) and waits for the next packet before repeating the steps.

FIG. 7 shows an embodiment of the invention in which the error rate is used as a signal quality variable measured from the selected device (s). In an embodiment, the minimum bit or frame error rate is determined for each of the selected devices (ie, each link) (step 71). In the receive control mode, the terminal calculates the bit or frame error rate for these selected devices that are received simultaneously. If the calculated error rate is greater than the corresponding minimum values, the receiver's performance, such as receiver sensitivity, may be degraded to reduce power consumption (step 76). Performance may be degraded based on the device and its error rate closest to each minimum value. If any error rate values are smaller than the corresponding minimum value, the performance of the receiver is improved (step 75). The media access control mode is similar to that described with respect to FIG.

8 illustrates the basic elements of a mobile terminal according to an embodiment of the present invention. The mobile terminal 80 includes a transceiver 81 providing at least one antenna 82, a control unit 83, user interface means 84 for generating a user interface through which the user can operate the terminal, and Storage means 85, which may comprise one or more smart cards 86, such as one of the identification modules described above. However, as mentioned above, the identification module is not included in the traditional WLAN terminal. The control unit performs the above-described control functions of the present invention, that is, the control logic blocks shown in FIG. 5 and controls the transceiver shown by the arrows in the figure. The storage means stores control information required for performance control, such as lookup table (s) indicating internal control operations for controlling performance and power consumption according to measured signal strength or error rate values and measured signal quality variables. Includes a MAC MIB or similar database that may include. The control unit obtains signal quality variables from the transceiver and stores them in memory.

The data processing environment of the control unit may be in common with that of an ordinary PC, and if an existing wireless terminal is provided at the appropriate interfaces for receiver sensitivity control, the control mechanism of the present invention is present at the existing terminal, eg. For example, it can be introduced individually into a multimedia card. The control mechanism, ie the program code which allows the control unit to control the performance of the receiver in the manner described above, is delivered as a separate plug-in software module which can be downloaded to the terminal via the network.

In addition, the above-described embodiments for controlling the sensitivity and the dynamic range of the receiver can be combined such that the sensitivity is controlled when there are no strong external obstacles, and when such obstacles are present in the vicinity of the terminal.

Although the present invention has been described above with reference to the examples shown in the accompanying drawings, it is apparent that the present invention is not limited to this, and may be modified by those skilled in the art without departing from the scope and spirit of the present invention. As noted above, the present invention can be used in any networks where the media access control mechanism includes functionality similar to the IEEE 802.11 Distributed Coordination Function (DCF). Therefore, the present invention can also be used in a system with centralized media access control if centralized control is not used continuously. Moreover, different physical transmission technologies such as Ultra Wide-Band (UWB) or Bluetooth may be used in these networks. The performance of the receiver can also be controlled in any manner that allows for the degradation in performance that is implemented to reduce receiver power consumption.

Claims (44)

A method for reducing power consumption in a wireless communication terminal, Selecting at least one communication device as a communication peer in a wireless communication system; Measuring a signal quality variable from at least one of the at least one communication device selected in the selection step, wherein each signal quality variable is measured based on a signal received from each one of the at least one communication device selected in the selection step Wherein at least one signal quality variable is obtained); Adjusting receiver performance based on at least one of the at least one signal quality variable obtained in the measuring step, wherein the adjusting step ensures reception of respective signals from the at least one communication device selected in the selecting step. To reduce power consumption during the process); Monitoring whether the transmission of the wireless communication terminal is coming; And Reconditioning the performance of the receiver to determine the availability of a common air medium at a performance level capable of detecting transmission of communication devices within the service area of the transmission of the wireless communication terminal, And said reconditioning step is performed when said monitoring step indicates that a transmission of said wireless communication terminal is coming. 10. The method of claim 1, wherein the step of regulating and the step of regulating includes adjusting the sensitivity of the receiver. 2. The method of claim 1, wherein the measuring step includes measuring the signal quality variable from each of the at least one communication device, wherein each measured signal quality variable is based on a signal strength received from the corresponding communication device. Displaying a method for reducing power consumption. 4. The method of claim 3, further comprising determining a device specific signal-to-noise-ratio for each of the at least one communication device, wherein each device-specific signal-to-noise ratio Indicating a signal to noise ratio value required for receiving the communication device considered. 5. The method of claim 4, further comprising determining a maximum amount of receiver noise allowed for each of the at least one communication device, wherein the maximum amount of receiver noise allowed for the communication device is determined by the device in the determining step. And based on the minimum signal-to-noise ratio determined for the device and the received signal strength measured for the device in the measuring step. 6. The method of claim 5, wherein the selecting step includes selecting a plurality of communication devices. 7. The method of claim 6, further comprising the step of selecting one of the plurality of communication devices, wherein the step of selecting comprises at a maximum amount of receiver noise determined for the at least one communication device in determining a maximum amount of the receiver noise. A method for reducing power consumption, characterized in that performed on the basis of. 8. The method of claim 7, wherein the step of adjusting comprises adjusting receiver sensitivity based solely on the selected communication device, wherein the step of adjusting is performed to receive the plurality of communication devices. Method for reducing. 7. The method of claim 6, wherein the step of adjusting includes simultaneously adjusting receiver sensitivity based on one of the plurality of communication devices. 3. The method of claim 2, wherein said reconditioning comprises maximizing receiver sensitivity. 2. The method of claim 1, further comprising determining transmit power for transmission of the wireless communication terminal. 12. The method of claim 11, wherein the step of reconditioning includes a substep of determining receiver sensitivity based on the determined transmit power. 13. The method of claim 12, further comprising: determining availability of common public media using the sensitivity determined in the sub-determining step; And And performing the transmission of the wireless communication terminal. 2. The method of claim 1, further comprising determining an interfering power received at the communication terminal, wherein the interfering power is indicative of the level of interference generated by external disturbances. How to make it. 15. The method of claim 14, wherein said step of regulating and said step of regulating include adjusting the dynamic range of said receiver. 15. The method of claim 14, wherein determining the interference power comprises determining a total co-channel power. 15. The method of claim 14, wherein determining the interference power comprises determining intermodulation power. 15. The method of claim 14, wherein determining the interference power comprises determining adjacent channel power. 16. The method of claim 15, further comprising determining a device specific signal to interference ratio for each of the at least one communication device, wherein each device specific signal to interference ratio is required to receive the considered communication device. Displaying a signal to interference ratio value. 20. The method of claim 19, wherein the step of adjusting comprises adjusting a dynamic range based on the interference power determined in the step of determining the interference power and the device specific signal to interference ratio of one of the at least one communication device. A method for reducing power consumption. 2. The method of claim 1, wherein the selecting step includes selecting an access point as the communication peer. 2. The method of claim 1, wherein said selecting step includes selecting at least one other wireless communication terminal as said communication peer. 5. The method of claim 4, wherein the determining step comprises calculating the minimum signal to noise ratio for each of the at least one wireless communication device and adding a predetermined margin to the minimum signal to noise ratio, respectively. Determining the device specific signal-to-noise ratio for the power consumption. 20. The apparatus of claim 19, wherein the determining step comprises calculating a minimum signal to interference ratio for each of the at least one wireless communication device and adding a predetermined margin to the minimum signal to interference ratio, respectively. Determining the device specific signal to interference ratio for the power consumption. The method of claim 1, wherein the adjusting step comprises at least one operation selected from the group comprising a decrease in bias current, a decrease in supply voltage, and a bypass of the selected receiver stage. . 2. The method of claim 1, wherein the step of adjusting comprises substeps of controlling several receiver blocks, each block being controlled individually. 27. The method of claim 26, wherein said controlling substep includes recovering control information for each block from a look-up table. 27. The method of claim 26, wherein said controlling substep includes calculating control information to minimize power consumption. The method of claim 1, wherein the measuring step comprises measuring the signal quality variable from each of the at least one communication device, wherein each signal quality variable indicates an error rate of a signal received from the corresponding communication device. A method for reducing power consumption. Selection means for selecting at least one communication device as a communication peer in a wireless communication system; First measuring means for measuring a signal quality variable from at least one of the at least one communication device (each signal quality variable being measured based on a signal received from each one of the at least one communication device, wherein at least One signal quality variables are obtained); First performance control to adjust receiver performance based on at least one of the at least one signal quality variable to cause a wireless communication terminal to receive respective signals from the at least one communication device having a reduced power consumption; Means; Monitoring means for monitoring whether transmission of the wireless communication terminal is coming; And Second performance control means for adjusting receiver performance to a performance level at which the terminal can detect transmission of communication devices within a service area of the transmission of the wireless communication terminal, the second performance control means being monitored. Means for being configured to operate when the indication of a transmission of the wireless communication terminal is coming. 31. The wireless communication terminal of claim 30, wherein the first and second performance control means are configured to control receiver sensitivity. 32. The wireless communication terminal of claim 31, wherein the at least one signal quality variables indicate signal strength. 33. The apparatus of claim 32, further comprising computing means for calculating a device specific signal to noise ratio for each of the at least one communication device, wherein each device specific signal to noise ratio is to be considered for receiving the considered communication device. A wireless communication terminal, characterized by displaying the required signal to noise ratio. 34. The apparatus of claim 33, wherein the first performance control means are allowed for each of at least one communication device based on the device specific signal to noise ratio determined for the device and the received signal strength measured for the device. And configure a maximum amount of receiver noise. 32. The apparatus of claim 31, wherein the first performance control means are further configured to select one of the at least one communication device and to adjust the receiver sensitivity based on the maximum amount of receiver noise allowed for the device. Wireless communication terminal. 32. The wireless communication terminal of claim 31, wherein the second performance control means are configured to maximize receiver sensitivity when transmission of the wireless communication terminal is approaching. 32. The wireless communication terminal of claim 31, wherein the second performance control means are configured to determine receiver sensitivity based on transmit power determined for transmission of the wireless communication terminal. 31. The wireless communication terminal of claim 30, wherein the first performance control means provides a look-up table indicative of acquired internal control measurements. 31. The wireless communication terminal of claim 30, wherein the second performance control means provides a look-up table indicative of acquired internal control measurements. 31. The wireless communication terminal of claim 30, further comprising second measuring means for measuring interference power received at the communication terminal, the interference power indicating an interference level generated by external disturbances. . 41. The wireless communication terminal of claim 40, wherein the first and second performance control means are configured to control the receiver dynamic range. 42. The apparatus of claim 41, wherein the first performance control means are further for selecting one of the at least one communication device and adjusting the dynamic range based on the interference power and a signal quality parameter corresponding to the selected device. And a wireless communication terminal. 31. The wireless communication terminal of claim 30, wherein the at least one signal quality variable indicates an error rate of a signal measured from the corresponding communication device. A first computer readable program code portion for causing at least one communication device to be selected as the communication peer for the wireless communication terminal; A second computer readable program code portion for causing the wireless communication terminal to adjust receiver performance based on signal quality parameters measured based on signals received from at least one of the at least one wireless communication device; A third computer readable program code portion for causing the wireless communication terminal to generate an indication when a transmission of the wireless communication terminal is coming; And A fourth computer readable program code portion for causing the wireless communication terminal to adjust receiver performance to a level at which the wireless communication terminal can detect transmitting communication devices within the transmission service area of the wireless communication terminal; And said fourth computer readable program code portion is operative in response to said indication, wherein said computer readable program code is embodied for controlling said wireless communication terminal.

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