Patent Description:
A reception apparatus may receive data from a transmission apparatus. In general, the reception apparatus may be unaware of when the transmission apparatus transmits data. In cases in which the reception apparatus waits for data to be transmitted from the transmission apparatus at all times, the reception apparatus may use a significantly great amount of power to receive the data. Accordingly, in an idle state, the reception apparatus may periodically monitor whether the transmission apparatus has transmitted data. Only when the transmission apparatus transmits the data may the reception apparatus shift from the idle state to an active state and receive the data.

For the above operation, the transmission apparatus may include a preamble within a frame to transmit the data. In the idle status, the reception apparatus may periodically attempt a detection of the preamble that may have been transmitted from the transmission apparatus. When the reception apparatus succeeds in detecting the preamble, the reception apparatus determines that data is ready to be transmitted from the transmission apparatus, and thus may shift from the idle state to the active state to receive the data.

In <CIT>, an apparatus and method for signal detection in a Broadband Wireless Access (BWA) system are provided, in which in a transmitter, a first preamble sequence generator generates preamble sequences, a low-Peak-to-Average Power Ratio (PAPR) preamble sequence selector selects a first low-PAPR preamble sequence from among the generated preamble sequences, a preamble sequence copier copies the first low-PAPR preamble sequence at least once and outputs the first low-PAPR preamble sequence and the at least one copy, a complex conjugator generates preamble sequences orthogonal to the first low-PAPR preamble sequence and the at least one copy by calculating complex conjugates of the first low-PAPR preamble sequence and the at least one copy, and a second preamble sequence generator generates at least one second low-PAPR preamble sequence using the first low-PAPR preamble sequence.

<CIT> specifies a multiple-input multiple-output (MIMO) wireless local area network (WLAN) system which includes a method for transmitting and receiving data using a MIMO decoding scheme. A method for receiving data includes receiving a preamble from one or more stations via a plurality of receiving antennas, estimating a wireless channel between the station and an access point based on the received preambles, detecting a collision associated with each station based on the received preambles, and decoding the data by referring to a wireless channel estimate if the collision is detected.

<CIT> specifies that a wireless device comprises a code-assignment module configured for assigning Golay codes to be used for spreading, a spreading module configured for spreading data with the Golay codes to produce a signal, wherein the Golay codes are randomly used to spread the data, and a transmitter configured for transmitting the signal. The wireless device may transmit a first beacon signal via a set of quasi-omni beam patterns, and a second beacon signal via a set directional beam patterns. The first beacon signal has a first transmission rate that is higher than the second beacon signal's the transmission rate. Extended Golay codes having zero periodic cross-correlation may be generated from a Golay code and a set of short sequences. A data block transmitted by the wireless device may comprise Golay codes and data portions, wherein every data portion is between two Golay codes and every Golay code is between two data portions.

<CIT> discloses an access point, AP, that transmits a beacon or an association message including a capability information element, IE, that indicates operation or support for a legacy preamble, high throughput, HT, stations HT STA preambles and a medium access control, MAC, packet transmission with HT protection mechanisms. If an AP does not support the HT STAs, it indicates this information in a beacon such that the HT STAs operate in legacy mode using a legacy preamble.

Conventional systems and methods use power inefficiently.

Other features and aspects may be apparent from the following detailed description, the drawings, and the claims.

Accordingly, various changes, modifications, and equivalents of the methods, apparatuses, and/or systems described herein will be suggested to those of ordinary skill in the art. The progression of processing steps and/or operations described is an example; however, the sequence of steps and/or operations is not limited to that set forth herein and may be changed as is known in the art, with the exception of steps and/or operations necessarily occurring in a certain order. Also, description of well-known functions and constructions may be omitted for increased clarity and conciseness.

<FIG> illustrates a diagram to describe an example of a method of transmitting and receiving data using a multi-class preamble structure.

According to an embodiment, a transmission apparatus (e.g., transmission apparatus <NUM> in the example of <FIG>, below) may transmit, to a reception apparatus (e.g., first reception apparatus <NUM> or second reception apparatus <NUM> in the example of <FIG>, below), a data frame containing data. In an idle state, the reception apparatus may detect a preamble included in the data frame. In response to the reception apparatus succeeding in a detection of the preamble, the reception apparatus may determine data is being transmitted from the transmission apparatus. In response to the data not being transmitted from the transmission apparatus, the reception apparatus may maintain the idle state and decrease a power communication. Conversely, in response to the data being transmitted from the transmission apparatus, the reception apparatus may shift from the idle state to an active state to receive the data.

The transmission apparatus may transmit data to a plurality of reception apparatuses having different characteristics (e.g., first reception apparatus <NUM> or second reception apparatus <NUM> in the example of <FIG>, below). For example, a first reception apparatus may be stably supplied with a power from a power socket, and the like. The first reception apparatus may receive data without a limitation on the power. A second reception apparatus may be supplied with the power using a battery, and the like. The second reception apparatus may have some constraints on receiving the data due to a limitation of the power.

The transmission apparatus may transmit different preambles designed based on characteristics of the respective reception apparatuses. Each of the reception apparatuses may detect a portion of or all of the preambles based on corresponding characteristics. For example, the first reception apparatus may detect both a first preamble and a second preamble. For example, the first reception apparatus, which may not be affected by the power limitation, may detect all the preambles, and may quickly receive data from the transmission apparatus. The second reception apparatus, which may be affected by the power limitation, may detect only the second preamble, and may effectively receive data.

Referring to <FIG>, a transmission apparatus may transmit, to a second reception apparatus, data frames <NUM> and <NUM> containing first preambles <NUM> and <NUM>, and a data frame <NUM> containing a second preamble <NUM>. In this instance, the second reception apparatus may not detect the first preambles <NUM> and <NUM>, and thus may not receive data included in the data frames <NUM> and <NUM> containing the first preambles <NUM> and <NUM>. The second reception apparatus may detect the second preamble <NUM>, and thus may receive data <NUM> included in the data frame <NUM> containing the second preamble <NUM>.

According to another embodiment, a first reception apparatus may detect only a first preamble, and may receive data from a transmission apparatus. A second reception apparatus may detect only a second preamble and receive data from the transmission apparatus.

<FIG> illustrates an example of multiple preambles.

Referring to <FIG>, a first preamble may be repeatedly transmitted during every first time interval <NUM>. A second preamble may be repeatedly transmitted during every second time interval <NUM> or <NUM>. A transmission apparatus may transmit all of the first preamble and the second preamble. Each of reception apparatuses may receive a preamble corresponding to a characteristic of a corresponding reception apparatus.

A length of the first time interval <NUM> may be different from a length of the second time interval <NUM> or <NUM>. As shown in <FIG>, the first time interval <NUM> may be an integer multiple of the second time interval <NUM> or <NUM>.

A first reception apparatus may receive preambles repeated during every first time interval <NUM>. Referring to <FIG>, the first reception apparatus may receive the first preamble and the second preamble repeated during every first time interval <NUM>.

A second reception apparatus may receive preambles repeated during every second time interval <NUM> or <NUM>. Referring to <FIG>, the second reception apparatus may receive the second preamble repeated during every second time interval <NUM> or <NUM>. However, the second reception apparatus may not receive the first preamble.

<FIG> illustrates an example of each reception apparatus receiving a first preamble.

A first reception apparatus may detect the first preamble by correlating a first correlation signal with a signal received from a transmission apparatus. A length of the first correlation signal may be the same as a length of a first time interval. For example, in response to the length of the first correlation signal being the same as a length of the first preamble, the first reception apparatus may detect preambles repeated during every first time interval.

Referring to <FIG>, the first reception apparatus may detect the first preamble after the first preamble is repeated twice.

A second reception apparatus may detect a second preamble by correlating a second correlation signal with the signal received from the transmission apparatus. A length of the second correlation signal may be the same as a length of a second time interval. For example, in response to the length of the second correlation signal being the same as a length of the second preamble, the second reception apparatus may detect preambles repeated during every second time interval.

However, in response to the length of the first preamble being an integer multiple of the length of the second correlation signal, the second reception apparatus may not detect the first preamble. Referring to <FIG>, the second reception apparatus may not detect the first preamble.

<FIG> illustrates an example of each reception apparatus receiving a second preamble.

The second preamble may be repeated during every second time interval. A length of a first time interval may be an integer multiple of a length of the second time interval. Accordingly, in response to an integer number of second preambles being combined, the second preamble may be repeated during every first time interval. Accordingly, in <FIG>, a first reception apparatus may detect the second preamble after the first time interval is repeated twice, using a first correlation signal.

A second reception apparatus may detect the second preamble after the second time interval is repeated twice.

<FIG> and <FIG> illustrate examples in which each reception apparatus may receive the preambles of <FIG>. The first reception apparatus may receive both the first preamble and the second preamble. The second reception apparatus may receive only the second preamble.

<FIG> illustrates an example of a transmission apparatus <NUM> according to the claimed invention.

The transmission apparatus <NUM> includes a first preamble transmitter <NUM>, a control signal transmitter <NUM>, and a second preamble transmitter <NUM>.

The first preamble transmitter <NUM> transmits, to a first reception apparatus <NUM>, a first preamble detectable by the first reception apparatus <NUM>.

The second preamble transmitter <NUM> transmits, to a second reception apparatus <NUM>, a second preamble detectable by the second reception apparatus <NUM>.

The first preamble transmitter <NUM> transmits the first preamble to the second reception apparatus <NUM>, and the second preamble transmitter <NUM> may transmit the second preamble to the first reception apparatus <NUM>. In one example, even though the second reception apparatus <NUM> may not detect the first preamble, the first reception apparatus <NUM> may detect the second preamble.

A length of the first preamble is an integer multiple of the second preamble.

The first reception apparatus <NUM> may denote a reception apparatus that may be stably supplied with a power from a power socket, and the like. The second reception apparatus <NUM> may denote a reception apparatus that may be supplied with the power using a battery, and the like. In one example, the first reception apparatus <NUM> may receive data without a limitation on the power, and the second reception apparatus <NUM> may have some constraints on receiving the data due to a limitation of the power.

As described above, the first reception apparatus <NUM> may detect both the first preamble and the second preamble. In response to the first reception apparatus <NUM> receiving data, the power may be unlimited and thus the first reception apparatus <NUM> may attempt a detection of the first preamble or the second preamble during every time interval in which the first preamble or the second preamble is transmitted. In response to the first reception apparatus <NUM> succeeding in a preamble detection, the first reception apparatus <NUM> may determine data is to be transmitted from the transmission apparatus <NUM>. Accordingly, the first reception apparatus <NUM> may shift from an idle state to an active state, and may receive data from the transmission apparatus <NUM>.

The second reception apparatus <NUM> may detect only the second preamble. The second reception apparatus <NUM> may attempt a detection of the second preamble during every time interval in which the second preamble is transmitted. The second reception apparatus <NUM> may attempt the detection of only the second preamble, and thus may decrease a power consumption compared to the first reception apparatus <NUM>. In response to the second reception apparatus <NUM> succeeding in the detection of the second preamble, the second reception apparatus <NUM> may determine data is to be transmitted from the transmission apparatus <NUM>. Accordingly, the second reception apparatus <NUM> may shift from the idle state to the active state and receive data from the transmission apparatus <NUM>.

The control signal transmitter <NUM> may transmit a control signal to each of the first reception apparatus <NUM> and the second reception apparatus <NUM>. Each of the first reception apparatus <NUM> and the second reception apparatus <NUM> may detect both the first preamble and the second preamble, or may detect only the first preamble according to the control signal.

<FIG> illustrates an example of a reception apparatus <NUM> according to the claimed invention.

The reception apparatus <NUM> includes a receiver <NUM>, a control signal receiver <NUM>, a first preamble detector <NUM>, and a second preamble detector <NUM>.

The receiver <NUM> receives, from a transmission apparatus <NUM>, a signal containing a first preamble or a second preamble.

The control signal receiver <NUM> receives a control signal from an upper layer. The control signal may include information associated with a preamble to be detected by the reception apparatus <NUM>.

The first preamble detector <NUM> may detect the first preamble.

The second preamble detector <NUM> may detect the second preamble.

In response to the reception apparatus <NUM> being in an idle state, the control signal receiver <NUM> may decrease a power consumption of the reception apparatus <NUM> by inactivating the first preamble detector <NUM> and the second preamble detector <NUM>, and by cutting off the power.

The transmission apparatus <NUM> may designate a preamble to be received by the reception apparatus <NUM>, using the control signal. The transmission apparatus <NUM> may transmit the control signal to the reception apparatus <NUM>. The upper layer of the reception apparatus <NUM> may recognize the control signal. The control signal receiver <NUM> may receive the control signal from the upper layer.

The control signal receiver <NUM> activates the first preamble detector <NUM> or the second preamble detector <NUM> according to the control signal. For example, in response to the control signal indicating, e.g., that "the reception apparatus <NUM> needs to detect the first preamble," the control signal receiver <NUM> activates the first preamble detector <NUM> during a time interval in which the first preamble is transmitted. As the second preamble detector <NUM> may not activate, and only the first preamble detector <NUM> may be activated, a power consumption of the reception apparatus <NUM> may decrease.

In response to the control signal indicating that "the reception apparatus <NUM> needs to detect the second preamble," the control signal receiver <NUM> decreases the power consumption by activating only the second preamble detector <NUM>.

A length of the first preamble is an integer multiple of a length of the second preamble. The first preamble detector <NUM> detects the first preamble as well as the second preamble.

<FIG> illustrates a non-claimed example of a reception apparatus <NUM>.

The reception apparatus <NUM> may include a receiver <NUM>, a first preamble detector <NUM>, a second preamble detector <NUM>, and a multiplexer (MUX) <NUM>.

The receiver <NUM> may receive, from a transmission apparatus <NUM>, a signal containing a first preamble or a second preamble.

The first preamble detector <NUM> may detect the first preamble included in the received signal. In response to the first preamble being included in the received signal, the first preamble detector <NUM> may succeed in a detection of the first preamble.

The second preamble detector <NUM> may detect the second preamble included in the received signal. In response to the second preamble being included in the received signal, the second preamble detector <NUM> may succeed in a detection of the second preamble.

The MUX <NUM> may select one of an output of the first preamble detector <NUM> and an output of the second preamble detector <NUM>, according to the control signal.

For example, the received signal may include the first preamble, and the first preamble detector <NUM> may detect the first preamble. In one example, the MUX <NUM> may select the output of the first preamble detector <NUM>, according to the control signal.

The received signal may include the second preamble, and the second preamble detector <NUM> may detect the second preamble. In one example, the MUX <NUM> may select the output of the second preamble detector <NUM>.

<FIG> illustrates still another non-claimed example of a reception apparatus <NUM>.

The reception apparatus <NUM> may include a preamble detector <NUM> and a receiver <NUM>.

The reception apparatus <NUM> may operate to detect both a first preamble and a second preamble, or may operate to detect only the second preamble.

A length of the first preamble may be an integer multiple of a length of the second preamble. In one example, the transmission apparatus <NUM> may repeatedly transmit the second preamble during a time interval in which the first preamble is transmitted.

The receiver <NUM> may receive data from the transmission apparatus <NUM>, depending on whether the first preamble or the second preamble is detected. In response to the preamble detector <NUM> succeeding in a detection of the first preamble or the second preamble, the receiver <NUM> may receive data from the transmission apparatus <NUM>.

The second reception apparatus <NUM> may detect the first preamble received from the transmission apparatus <NUM>. In response to the second reception apparatus <NUM> succeeding in the detection of the first preamble, the second reception apparatus <NUM> may receive second data from the transmission apparatus <NUM>.

<NUM>) In response to the reception apparatus <NUM> operating to detect only the first preamble:
The preamble detector <NUM> may detect the second preamble received from the transmission apparatus <NUM>. The second preamble may be a preamble detectable by both the reception apparatus <NUM> and the second reception apparatus <NUM>. The first preamble may be a preamble detectable by only the reception apparatus <NUM>.

The receiver <NUM> may receive data from the transmission apparatus <NUM>, depending on whether the first preamble is detected. In response to the preamble detector <NUM> succeeding in a detection of the first preamble, the receiver <NUM> may receive data from the transmission apparatus <NUM>.

The second reception apparatus <NUM> may detect the first preamble or the second preamble received from the transmission apparatus <NUM>. In response to the second reception apparatus <NUM> succeeding in the detection of the first preamble or the second preamble, the second reception apparatus <NUM> may receive second data from the transmission apparatus <NUM>.

<FIG> illustrates a data transmission method according to the invention.

In operation <NUM>, a transmission apparatus, e.g., transmission apparatus <NUM> in <FIG>, transmits a first preamble and first data to a first reception apparatus, e.g., first reception apparatus <NUM> in <FIG>.

In operation <NUM>, the transmission apparatus transmits a second preamble and second data to the first reception apparatus and to a second reception apparatus, e.g., second reception apparatus <NUM> in <FIG>.

The second preamble may be a preamble detectable by both the first reception apparatus and the second reception apparatus. The first preamble may be a preamble detectable only by the first reception apparatus. A length of the first preamble is an integer multiple of a length of the second preamble.

The transmission apparatus may repeatedly transmit the second preamble during a time interval in which the first preamble is transmitted.

The first reception apparatus may detect both the first preamble and the second preamble. In response to the first reception apparatus succeeding in a detection of the first preamble, the first reception apparatus may receive the first data. In response to the first reception apparatus succeeding in a detection of the second preamble, the first reception apparatus may receive the second data.

The second reception apparatus may detect the second preamble. In response to the second reception apparatus succeeding in the detection of the second preamble, the second reception apparatus may receive the second data.

The first reception apparatus may denote a reception apparatus that may be stably supplied with a power from a power socket, and the like. The second reception apparatus may denote a reception apparatus that may be supplied with the power using a battery and the like. In one example, the first reception apparatus may receive data without a limitation on the power, and the second reception apparatus may have some constraints on receiving the data due to a limitation of the power.

The second reception apparatus may operate only during a time interval in which the second preamble is transmitted, and thus may decrease a power consumption in receiving data.

<FIG> illustrates an example of a data reception method.

In operation <NUM>, a reception apparatus receives, from a transmission apparatus, a signal containing a first preamble or a second preamble.

The first preamble is a preamble detectable by only the first reception apparatus, and the second preamble is a preamble detectable by the first reception apparatus and the second reception apparatus. A length of the first preamble is an integer multiple of a length of the second preamble. The transmission apparatus may repeatedly transmit the second preamble during a time interval in which the first preamble is transmitted.

In operation <NUM>, the reception apparatus receives a control signal from the transmission apparatus. The control signal may include information associated with a preamble to be received by the reception apparatus.

In operation <NUM>, the reception apparatus detects the first preamble or the second preamble according to the control signal.

The control signal may include information associated with one of the first preamble and the second preamble. The reception apparatus may detect only one of the first preamble and the second preamble according to the control signal. The reception apparatus may include a first preamble detector to detect the first preamble and a second preamble detector to detect the second preamble. The reception apparatus may decrease a power consumption by inactivating one of the first preamble detector and the second preamble detector according to the control signal.

In operation <NUM>, the reception apparatus receives data from the transmission apparatus, depending on whether the first preamble or the second preamble is detected.

<FIG> illustrates another example of a data reception method.

In operation <NUM>, a reception apparatus may detect a first preamble or a second preamble received from a transmission apparatus.

The second preamble may be a preamble detectable by both the reception apparatus and a second reception apparatus, and the first preamble may be a preamble detectable by only the reception apparatus.

A length of the first preamble may be an integer multiple of a length of the second preamble. The transmission apparatus may repeatedly transmit the second preamble during a time interval in which the first preamble is transmitted.

In operation <NUM>, the second reception apparatus may detect the second preamble.

In operation1120, the reception apparatus may receive data from the transmission apparatus, depending on whether the first preamble or the second preamble is detected. In response to the reception apparatus succeeding in a detection of the first preamble, or in response to the reception apparatus succeeding in a detection of the second preamble, the reception apparatus may receive data from the transmission apparatus.

In response to the second reception apparatus succeeding in the detection of the second preamble, the second reception apparatus may receive data from the transmission apparatus.

The second reception apparatus may operate to detect the second preamble only during a time interval in which the second preamble is transmitted, and may not operate during a time interval in which the first preamble is transmitted. Accordingly, in response to receiving data, it may be possible to decrease a power consumption with respect to a data reception.

According to embodiments, it may be possible to decrease a power consumption of a reception apparatus in an idle state.

According to embodiments, it may be possible to increase a standby time of a reception apparatus.

It should be appreciated that any of the above devices may perform any of the above methods, as consistent with the above disclosure.

The processes, functions, methods and/or software described above may be recorded, stored, or fixed in one or more computer-readable storage media that includes program instructions to be implemented by a computer to cause a processor to execute or perform the program instructions. The media and program instructions may be those specially designed and constructed, or they may be of the kind well-known and available to those having skill in the computer software arts. Examples of computer-readable media include magnetic media, such as hard disks, floppy disks, and magnetic tape; optical media such as CD-ROM disks and DVDs; magneto-optical media, such as optical disks; and hardware devices that are specially configured to store and perform program instructions, such as read-only memory (ROM), random access memory (RAM), flash memory, and the like. Examples of program instructions include machine code, such as produced by a compiler, and files containing higher level code that may be executed by the computer using an interpreter. The described hardware devices may be configured to act as one or more software modules in order to perform the operations and methods described above, or vice versa. In addition, a computer-readable storage medium may be distributed among computer systems connected through a network and computer-readable codes or program instructions may be stored and executed in a decentralized manner.

As a non-exhaustive illustration only, the device described herein may refer to mobile devices such as a cellular phone, a personal digital assistant (PDA), a digital camera, a portable game console, and an MP3 player, a portable/personal multimedia player (PMP), a handheld e-book, a portable tablet and/or laptop PC, a global positioning system (GPS) navigation, and devices such as a desktop PC, a high definition television (HDTV), an optical disc player, a setup and/or set top box, and the like consistent with that disclosed herein.

A computing system or a computer may include a microprocessor that is electrically connected with a bus, a user interface, and a memory controller. It may further include a flash memory device. The flash memory device may store N-bit data via the memory controller. The N-bit data is processed or will be processed by the microprocessor and N may be <NUM> or an integer greater than <NUM>. Where the computing system or computer is a mobile apparatus, a battery may be additionally provided to supply operation voltage of the computing system or computer.

It will be apparent to those of ordinary skill in the art that the computing system or computer may further include an application chipset, a camera image processor (CIS), a mobile Dynamic Random Access Memory (DRAM), and the like. The memory controller and the flash memory device may constitute a solid state drive/disk (SSD) that uses a non-volatile memory to store data.

Claim 1:
A transmission apparatus (<NUM>), comprising:
a first preamble transmitter (<NUM>) configured to transmit a first preamble and first data;
a second preamble transmitter (<NUM>) configured to transmit a second preamble and second data,
a control signal transmitter (<NUM>) configured to transmit a control signal to a reception apparatus indicating whether the reception apparatus needs to detect the first or the second preamble;
wherein a length of the first preamble is an integer multiple of a length of the second preamble, said integer multiple being larger than one.