JP2006500882A - Ad hoc wireless network communication method and electronic device using channel determined by receiver and reference signal transmitted - Google Patents

Abstract

An electronic device for communicating within a wireless ad hoc network and a multiple access system (such as a mobile telephone communication system) is disclosed. For example, the disclosed transmitter transmits data on a first channel to a first receiver in an ad hoc wireless network (or multiple access system), and on a second channel that is different from the first channel. Can transmit data to a second receiver in the ad hoc wireless network (or multiple access system). Here, the first and second channels are determined by respective receivers that receive the first and second transmission data. Thus, communication between a transmitter and various receivers in an ad hoc wireless network (or multiple access system) can be performed simultaneously. Related receivers, methods, computer program products, and systems for communication are also disclosed.

Description

(Claim of priority and cross-reference to related applications)
This application is based on US Provisional Patent Application No. 60 / 412,244 entitled “Method and Apparatus for Chaotic Radio Communication” filed on September 20, 2002, and “Ultra-large processing” filed on October 17, 2002. US Provisional Patent Application No. 60 / 419,151 entitled "gain system applying time offset" and "Ultra-large processing gained patent" entitled US Patent Application No. 60 / 419,151 filed Oct. 17, 2002. Claims priority of application 60 / 419,152. The entire text of the above application is incorporated herein by reference.

  The present invention relates generally to the field of communications, and more particularly to wireless communications.

  Many existing communication systems are considered to be highly structured. For example, in a cellular telephone system such as GSM, UMTS, or CDMA2000, the radio base station controls the transmission between the mobile radio and the wired backbone. The infrastructure for controlling the system can reside in a public land mobile network (PLMN) that can include subsystems such as a base station controller (BSC) and a mobile switching center (MSC). . Communication with the mobile radio is provided on a control channel defined by the system. Connection setup, channel assignment, handover, and other types of support functions can be controlled from the BSC and MSC.

  FIG. 1 illustrates a conventional system that coordinates the operation of several base stations in close proximity to reduce interference between mobile radios and provides a handover when the mobile radio moves across coverage area. . In particular, this system can handle problems related to mobile communication that occur when the system is used, such as wireless interface, roaming, authentication, and the like. The system can be disconnected from a traditional wired backbone such as the public switched telephone network (PSTN), but can interface to the backbone via a gateway (GMSC). As shown in FIG. 1, normally only the connection between the mobile radio and the base station (ie, the last segment of the call) is wireless.

  FIG. 2 shows a wireless extension function of a wired backbone such as the above-described PSTN. Since the wired backbone does not support mobile communications, these types of systems may not have the BSC and MSC subsystems shown in FIG. Some examples of wired backbone wireless extensions include DECT (PSTN / ISDN wireless extension) and IEEE 802.11, which is a wireless extension of Ethernet.

  Many of the above systems allow multiple users to access the system at essentially the same time. Access can be provided to a plurality of users, for example, by dividing a radio band into a plurality of channels. These types of systems are also referred to as multiple access systems that can be provided using the various methods shown in FIGS.

FIG. 3 shows an analog type of multiple access, commonly referred to as frequency division multiple access (FDMA), where access from N users is provided by N different frequencies ω _i . According to FIG. 3, N separate channels are provided at different frequencies as indicated by equally spaced carriers of different frequencies ω _i . The information signal (TX signal i) generated by each user modulates each carrier ω _i to provide a respective transmission signal. The transmitted signal can be received by the receiver by demodulating the transmitted signal using the same carrier frequency ω _i and processed by a low pass filter (LP filter) to provide the received signal (RX signal i). The bandwidth of the transmitted signal combined with the carrier spacing can determine the interference between adjacent channels. Advanced Mobile Phone System (AMPS), Nordic Mobile Phone (NMT) System, and Extended Total Access System (ETACS) are examples of FDMA based systems.

  In FDMA, the channel is confined to the intended channel, for example, to reduce interference, with appropriate spacing between adjacent carriers (called orthogonality). The relative positions of the carriers remain in a fixed relationship to each other (ie, the channels must not drift toward or away from each other). One way to reduce drift is to use a stable crystal oscillator as a reference for the frequency synthesizer inside the mobile radio.

Multiple users can access media based on time using digital communication systems such as Global System for Mobile Communications (GSM) and D-AMPS. Such systems are commonly referred to as time division multiple access (TDMA) systems. An example is shown in FIG. As shown in FIG. 4 can be assigned one of the N time slots t _i to each of N users. The transmitter transmits each signal (TX signal i) during each assigned time. Similarly, the receiver receives a signal (RX signal i) during the assigned time slot. In some TDMA systems as shown in FIG. 4, the channel provided by the carrier is divided into eight time slots. A channel can be defined by carrier frequency and time slot. Different users can be supported by different channels (ie, combinations of specific frequencies and assigned time slots). There is also known a method of combining TDMA and FDMA modes in which a plurality of carrier frequencies are divided into a plurality of time slots. Thus, a channel can be specified by one of the frequencies combined with one of the time slots.

  In TDMA, channel orthogonality can be provided by preventing consecutive time slots, which are enabled using a stable clock in the transceiver, from overlapping each other. In addition to the specific transmitter and receiver pair being synchronized in the system, different receivers are also synchronized with each other and the time slot assigned to one mobile radio is assigned to another mobile radio. Drifting to a new time slot can be prevented. Usually this can be achieved by synchronizing all mobile radios to a central control unit such as a base station.

It is also known to provide multiple access communications using a technique commonly referred to as code division multiple access (CDMA), such as systems using direct sequence CDMA (DS-CDMA) or direct sequence spread spectrum (DSSS). . As shown in FIG. 5, in DS-CDMA, transmission information (TX signal i) is spread with a high-speed spreading code (or signature) S _i associated with a specific transmitter i. Within the receiver, the signal is correlated using the same spreading code S _i and the signal can be despread to the original format (RX signal i). Usually, the spreading codes assigned to the transmitters are orthogonal to each other. If the spreading code used by the receiver does not match the spreading code used by the transmitter, the received signal may not be correctly despread and therefore may not be decoded. The DS-CDMA technique is used, for example, in IS-95, UMTS and CDMA2000. Conventional spread spectrum processing is described, for example, in McGraw-Hill, In. Published, 1994, Marvin K. Simon et al., "Spread spectrum communications handbook" ISBN 0-07-057629-7, pp. 7-117.

As shown in FIG. 6A, it is known to provide multiple access communication using a technique generally called frequency hopping CDMA (FH-CDMA). According to FIG. 6A, each of the N transmitters in the multiple access system divides the information to be transmitted into different segments and transmits each of the different segments at a carrier frequency that varies with time. A “hop pattern” defines which carrier frequency is used at which time for data transmission. In particular, over time, each transmitter basically hops (or switches) between carriers according to a pseudo-random hopping code, C _i (Ω, t), unique to a particular transmitter.

Only receivers that apply the same hopping code C _i applied at the time of transmission remain synchronized with the transmitter that transmitted the data and are therefore the only receivers that can decode the information. The example table of FIG. 6B shows an example of a hopping pattern in which N transmitters switch frequencies as a function of hopping codes applied by different transmitters (and receivers) as a function of time.

  One type of problem encountered with both DS-CDMA and FH-CDMA type systems is acquisition or initial code synchronization. If the spreading code is not synchronized with the receiver signal, accurate despreading may not be provided. Synchronization can be particularly difficult in situations where the signal to noise ratio (SNR) is low. As a result, synchronization is a time consuming process. This becomes a problem in the case of an asynchronous service where a synchronous phase is required every time a transmission is newly transmitted in a “burst”.

Furthermore, acquisition delay can be an obstacle when high interference immunity is desired. The processing gain (PG) in a direct sequence spread spectrum system can be defined as the ratio of signal to noise ratio (SNR) before and after despreading.
PG _{= SNR} despread _/ SNR _spread

The above equation means that the SNR before despreading is inversely proportional to the processing gain. When the processing gain is large, the SNR _spread becomes small. The SNR _de-spread after despreading is typically about 5-10 dB. For example, if the SNR _de-spread is about 8 dB and the desired processing gain is about 20 dB, the SNR _spread is about -12 dB. In other words, under the above conditions, the signal is buried in noise. Since acquisition is performed prior to signal despreading, synchronization is performed with a small SNR _spread . Furthermore, the smaller the SNR _spread , the longer it takes to capture. Therefore, the attractive extra-large processing gain system due to its high interference immunity suffers from the length of acquisition delay.

  In CDMA, channel orthogonality can be provided by the correlation characteristics of different codes used by mobile radios. However, code orthogonality can only be provided for certain phase differences between different codes, obtained by synchronizing different transceivers. Furthermore, this is limited to the story of DS-CDMA and FH-CDMA.

  An overview of another type of wireless system commonly referred to as an “ad hoc” system is shown in FIG. In contrast to many systems described above, ad hoc systems have little or no structure. A suitable device can establish a connection directly with another unit without the intervention of a base station or other central controller. Different connections can be established independently without coordination.

  FIG. 8 shows an example of an ad hoc system known as “Bluetooth” in which a single channel is shared by several devices in an ad hoc network. According to FIG. 8, each of the ad hoc networks 805A-D can operate independently of each other. The master device in each ad hoc network establishes a single channel that all devices in the ad hoc network use for communication. For example, if device 810A is the master of ad hoc network 805A, devices 815A and 820A communicate on the channel determined by master device 810A. Furthermore, only one device can transmit at a time within the ad hoc network 805A. Master device 810A does not control communications performed within ad hoc networks 805B-805D.

  Frequency hopping code division multiple access (FH-CDMA) techniques can be used by different ad hoc networks in close proximity to each other. When using FH-CDMA, each ad hoc master can define a unique hopping sequence for the associated ad hoc network to reduce interference with other ad hoc networks.

Bluetooth is available at www. Bluetooth. com , detailed information is available from Ericsson Review, a publication by Haartsen entitled "Bluetooth-The Universal Radio Interface for Ad-hoc, Wireless Connectivity". 3, 1998, pp. 110-117. Both of the above applications are incorporated herein by reference in their entirety.

  The unstructured nature of ad hoc systems such as Bluetooth can cause problems that do not occur with the other types of mobile systems described above. For example, in an ad hoc system, interference is hardly controlled. Because coordination and synchronization are not performed, the channels are not orthogonal, which results in problems when using the conventional multiple access method described above. Furthermore, since the transmission power and the distance between the receiver and the interference source cannot be controlled, the interference has a reception power larger than the reception power of the intended signal. This is sometimes called a “far-far problem”. This is because the transmitter power is high or because the distance between the transmitter and the receiver is relatively small, the leakage between signals is large and even frequency-divided signals interfere with each other. It is a problem that there is.

  FIG. 9A shows a situation in which the above perspective problem appears. In particular, transmitter 905 in communication with receiver 910 is subject to interference by device 915. As shown in FIG. 9A, device 915 may be much closer to receiver 910 and have higher output power than transmitter 905. Although device 915 is transmitting at a different frequency than transmitter 905, the spectral leakage that enters the channel filter of receiver 910 is large enough to interfere with the reception of the signal from transmitter 905. The signal of device 915 may also saturate receiver 910, which is sometimes referred to as desensitization or blockage.

  Another difficult problem that may occur within an ad hoc system is the so-called “hidden node” problem shown in FIG. 9B. The hidden node problem refers to a situation in which the transmitter 905 and the device 920 are not in communication with each other, but are both in communication with another device 910. When the transmitter 905 needs to transmit to the device 910, and therefore first determines whether the channel is free, the transmitter 905 will be 910 and 920 because the device 920 is out of range of the transmitter 905. May not be able to recognize that they are currently communicating. Therefore, the transmitter 905 believes that the channel is idle and starts transmitting. This hinders current communication between devices 910 and 920. As described above, the device 920 may not be detected from the mobile radio 905 because it is out of the communication range.

  Another difficult problem that can occur in an ad hoc system is the identification of the device to which the ad hoc is connected. A discovery process can be performed to determine which devices are in range and which connections can be established. In particular, an ad hoc device can always scan the wireless interface to detect configuration messages. This increases the power consumption of the ad hoc device.

  In addition, many of these systems also require a connection to be established prior to data transfer. If the data transmission interval is short, the established connection may be maintained. On the other hand, if the spacing is relatively long, it is beneficial to terminate the connection to reduce power consumption and interference. However, when the connection is terminated, there is an indirect cost of establishing a new connection before the next data transmission. Furthermore, if a large processing gain is desired, long acquisition and synchronization delays can prevent the system from disconnecting every data transfer. Various problems occurring in the above-described ad hoc system can be solved by a diffusion technique using an extremely large processing gain (super extra large processing gain) as described below.

  Embodiments of the present invention provide methods, electronic devices, and systems for systems for communication within wireless ad hoc networks and multiple access systems (such as mobile telephone communication systems). For example, in some embodiments of the present invention, a transmitter transmits data to a first receiver in an ad hoc wireless network (or multiple access system) over a first channel, and the first channel Data can be transmitted to a second receiver in the ad hoc wireless network (or multiple access system) on a second channel different from. Thus, communication between a transmitter and various receivers in an ad hoc wireless network (or multiple access system) can be performed simultaneously.

  Further, in some embodiments of the invention, the channel over which the transmitter communicates with the receiver is determined by the receiver. For example, the transmitter can request the identifier of the channel from which the receiver receives data. In response, the receiver can transmit its channel identifier to the transmitter, and the transmitter can transmit data to the receiver using the receiver's channel identifier.

  Different channels for receivers in an ad hoc wireless network (or multiple access system) can be provided by different functions or offsets. For example, in some embodiments of the invention, a first receiver in an ad hoc wireless network (or multiple access system) can designate a channel that can provide data as a first offset, and a second receiver Specify the second channel to receive data as an offset of 2. Accordingly, the transmitter can communicate with the first receiver by transmitting using the first offset, and can communicate with the second receiver by transmitting using the second offset. Furthermore, since the first and second offsets provide different channels on which communications can be performed, transmissions to the second receiver are not detected by the first receiver.

In some embodiments of the invention, the offset is a frequency offset) ω. For example, a first receiver in an ad hoc wireless network (or multiple access system) can specify a _first frequency offset (ω ₁ ) used by a transmitter attempting to transmit data to the first receiver. A second receiver in the ad hoc wireless network (or multiple access system) can specify a _second frequency offset) ω ₂ that can provide data to the second receiver. Thus, the transmitter can transmit to the first receiver using the _first frequency offset) ω ₁ and can transmit to the second receiver using the _second frequency offset) ω ₂ .

In some further embodiments of the present invention, the offset is a time offset) τ. Thus, the first receiver can define the first channel as a first time offset) τ ₁ and the second receiver can designate the second channel as a second time offset) τ ₂ . As a result, the transmitter using the first time offset) tau ₁ be sent to the first receiver can be transmitted to the second receiver using the second time offset) tau _2.

  In some further embodiments of the present invention, the reference signal (or spreading code) used to spread the transmitted information signal is transmitted to the receiver as a component of the transmitted composite signal. The receiver can despread the received signal implicitly using the reference signal contained in the composite signal. No knowledge of the reference signal is necessary on the receiver side. Thus, embodiments of the present invention can use essentially (or effectively) random and very long reference signals as spreading codes. The random nature of the reference signal and its length provide a very low correlation. Thus, the large spread provided by the reference signal generally provides a “super extra processing gain” for the received signal. Furthermore, since the reference signal is transmitted along with the data, the receiver can quickly despread the received signal because it does not require acquisition with a low SNR.

  In some embodiments of the invention, the reference signal is modulated with a frequency offset associated with some embodiments described herein. In another embodiment of the invention, the composite signal includes a reference component and an information component, one of the components being delayed by a time offset as described herein with respect to the other.

  Hereinafter, the present invention will be described in detail with reference to the accompanying drawings showing embodiments of the present invention. However, the present invention may be implemented in different forms and should not be construed as limited to the embodiments set forth herein. On the contrary, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

  The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The singular nouns used in the description of the present invention and the appended claims also include the plural unless the context clearly dictates otherwise.

  As used herein, the terms “comprising” and / or “comprising” specify the presence of the described feature, integer, step, action, element, and / or component, but one or more The presence or addition of other features, integers, steps, actions, elements, components and / or groups thereof is not excluded.

  Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. All publications, patent applications, patents and other references mentioned herein are hereby incorporated by reference in their entirety.

  As will be apparent to those skilled in the art, the present invention may be embodied as a method, an electronic device such as a wireless telephone, a system, and / or a computer program product. Therefore, the present invention can be realized in a hardware embodiment, a software embodiment, or an embodiment combining software and hardware.

  The present invention is disclosed using (block and flow) diagrams. It should be understood that each block (in the flowchart and block diagram) and combinations of blocks can be implemented using computer program instructions. These program instructions are provided to a processor circuit in the mobile user terminal or system, and the instructions executed on the processor circuit create a means for performing the functions specified in one or more blocks.

  Computer program instructions can be executed by a processor circuit, such as a digital signal processor, which causes a series of operational steps to be performed by the processor circuit to generate a computer-implemented process, with the instructions executed on the processor circuit in one or more blocks Provide steps to perform the specified function. Therefore, each block supports a combination of means for executing the designated function, a combination of steps for executing the designated function, and a program instruction for executing the designated function. It should also be understood that each block and combination of blocks can be implemented by a specific function or combination of steps, or by a special purpose hardware-based system that executes special purpose hardware and computer instructions. .

  Furthermore, the present invention may take the form of a computer program product on a computer-usable storage medium having computer-usable program code embodied in the medium. Any suitable computer readable medium may be used including hard disks, CD-ROMs, optical storage devices, or magnetic storage devices.

  Computer program code or “code” or instructions that perform the operations of the present invention can be written in an object-oriented programming language such as JAVA or various other programming languages. Software embodiments of the present invention do not depend on embodiments using a particular programming language.

  These computer program instructions may be stored in a computer readable memory that causes a computer or other programmable data processing device to function in a particular manner, with the instructions stored in the computer readable memory being in one or more illustrated blocks. Enables manufacture of an article of manufacture that includes instruction means for performing a specified function.

  The outline of the present invention will be described by taking an electronic device such as a wireless telephone as an example. In such electronic devices, the antenna can emit electromagnetic waves generated by a transmitter located within the electronic device. The electromagnetic waves propagate in the wireless propagation medium and are received by the receiver via one or more antennas. The receiver described herein can be included in a transmitter to provide a transceiver for an electronic device.

  As used herein, the term “electronic device” includes, inter alia, single or dual mode cellular radiotelephones with or without a multiline display, cellular radiotelephones and data processing, facsimile and Personal communication system (PCS) terminals that can be combined with data communication functions, headsets, tablets or pen computers, wireless telephones (eg, devices also called “smart phones”), pagers, the Internet A personal data assistant ("PDA") including an intranet access, web browser, organizer, calendar and / or global positioning system (GPS) receiver and a conventional laptop computer, Including any electronic device configured to operate within a wireless ad hoc wireless network or multiple-access system, including desktop computers and / or general purpose desktop computers, tablet computers, and other equipment including transceivers Can do. Other types of electronic devices can also be included.

  Embodiments of the present invention can provide methods, electronic devices, systems, and computer program products for communicating within wireless ad hoc networks and multiple access systems (such as mobile wireless communication systems). For example, in some embodiments of the present invention, a transmitter transmits data to a first receiver in an ad hoc wireless network (or multiple access system) over a first channel, and the first channel Data can be transmitted to a second receiver in the ad hoc wireless network (or multiple access system) on a second channel different from. Here, the first and second channels are determined by respective receivers that receive the first and second transmission data. Thus, communication between a transmitter and various receivers in an ad hoc wireless network (or multiple access system) can be performed simultaneously.

  Further, in some embodiments of the invention, the channel over which the transmitter communicates with the receiver is determined by the receiver. For example, the transmitter can request the identifier of the receiver to which the data is sent. In response, the receiver can transmit its identifier to the transmitter, and the transmitter can use the receiver identifier to transmit data on the channel based on the receiver identifier.

  Different channels for receivers in an ad hoc wireless network (or multiple access system) can be provided by different functions or offsets. For example, in some embodiments of the present invention, a first receiver in an ad hoc wireless network (or multiple access system) transmits data to the receiver on a first channel designated as a first offset. And the second receiver specifies a second identifier for transmitting data to the receiver on a second channel specified as a second offset different from the first offset . Accordingly, the transmitter can communicate with the first receiver by transmitting using the first offset, and can communicate with the second receiver by transmitting using the second offset. Furthermore, since the first and second offsets provide different channels on which communications can be performed, transmissions to the second receiver are not received by the first receiver.

In some embodiments of the invention, the offset is a frequency offset) ω. For example, a first receiver in an ad hoc wireless network (or multiple access system) can specify a _first frequency offset (ω ₁ ) used by a transmitter attempting to transmit data to the first receiver. A second receiver in the ad hoc wireless network (or multiple access system) can specify a _second frequency offset) ω ₂ that provides data to the second receiver. Thus, the transmitter can transmit to the first receiver using the _first frequency offset) ω ₁ and can transmit to the second receiver using the _second frequency offset) ω ₂ .

In yet another embodiment of the invention, the offset is a time offset) τ. Thus, the first receiver can define the first channel as a first time offset) τ ₁ and the second receiver can designate the second channel as a second time offset) τ ₂ . As a result, the transmitter using the first time offset) tau ₁ be sent to the first receiver can be transmitted to the second receiver using the second time offset) tau _2.

  In yet another embodiment of the invention, a reference signal (or spreading code) for spreading the transmitted information signal is transmitted to the receiver as a component of the composite signal to be transmitted. The receiver can despread the received signal implicitly using the reference signal contained in the composite signal. No knowledge of the reference signal is necessary on the receiver side. Thus, embodiments of the present invention can use essentially (or effectively) random and very long reference signals as spreading codes. The random nature of the reference signal and its length provide a very low correlation. Thus, the large spread provided by the reference signal generally provides a “super extra processing gain” for the received signal. Furthermore, since the reference signal is transmitted with the data, the receiver can quickly despread the received signal.

  In some embodiments of the invention, the reference signal is modulated with a frequency offset associated with some embodiments described herein. In another embodiment of the present invention, the reference signal component that is part of the composite signal (including the reference signal component and the modulated information signal component) is delayed by the time offset described herein.

  FIG. 10 is a schematic diagram illustrating a plurality of electronic devices operating within an established ad hoc network 1000 according to an embodiment of the present invention. It will be further understood that the electronic device described herein includes a transmitter circuit (for data transmission) and a receiver circuit (for data reception) in the ad hoc network 1000.

  According to FIG. 10, each electronic device in the ad hoc network 1000 defines an associated unique channel that can receive data from any other suitable electronic device. For example, the first electronic device 1005 has an associated unique channel 1030 for receiving data within the ad hoc network 1000. Any other electronic device in the ad hoc network 1000 can transmit data to the first electronic device 1005 by transmitting data on the channel 1030. Further, the second electronic device 1010 has an associated unique channel 1020 that can receive data within the ad hoc network 1000. For example, the first electronic device 1005 can transmit data to the second electronic device 1020 by transmitting data on a unique channel 1020 associated with the second electronic device 1010. The third electronic device 1015 has an associated unique channel 1025 that can receive data within the ad hoc network 1000. For example, the second electronic device 1010 can transmit data to the third electronic device 1015 over a unique channel 1025.

  A transmitter can transmit to a receiver in the ad hoc network 1000 without checking whether another device is transmitting, for example, when multiple transmitters transmit to a single receiver. May occur. Accordingly, embodiments of the present invention may use an acknowledgment method that, for example, transmits an acknowledgment signal to the transmitter when the receiver successfully receives data from the transmitter. If the transmitter does not receive an acknowledgment from the intended receiver, the transmitter may attempt to retransmit the same data to the receiver after a period of time. This method can be used to choose to terminate the conflicting transmissions being performed by the receiver.

  Thus, communication can be performed between any electronic device that uses a pair of unique channels associated with each of the devices. In other words, dual data transmission can be provided using a pair of unidirectional channels where each channel of the pair is unique to one of the electronic devices. For example, communication between the first electronic device 1005 and the second electronic device 1010 can be performed on a pair of channels 1020 and 1030, providing dual communication. Furthermore, communication between electronic devices can be performed at any time without coordination with any other communication in the ad hoc network or any other prior connection between devices. For example, the first electronic device 1005 can transmit to any other electronic device without first checking whether the other device is in communication. The problem of mutual interference can be addressed by removing or reducing the effects of unwanted signals within the super-large processing gain receiver described herein.

  FIG. 11 is a schematic diagram illustrating data communication in an ad hoc network 1000 according to an embodiment of the present invention. In particular, in embodiments of the present invention, data can be transmitted to the receiver of any electronic device in the ad hoc network 1000 by transmitting the data on a unique channel to the target electronic device. For example, according to FIG. 11, the first electronic device 1005 transmits data on a unique channel 1020 determined by the second electronic device 1010 to the receiver of the second electronic device 1010. Can send data. Further, the first electronic device 1005 can transmit data to the receiver of the third electronic device 1015 by transmitting data on the unique channel 1025 determined by the third electronic device 1015. The second electronic device 1010 transmits data to either the first electronic device 1005 or the third electronic device 1015 by transmitting data on the unique channel 1030 or the unique channel 1025, respectively. it can. Similarly, the third electronic device 1015 can transmit data to the first and second electronic devices 1005, 1010 by transmitting data on the unique channel 1030 or 1020, respectively.

  An electronic device operating in the ad hoc network 1000 can perform a discovery phase in which any electronic device can determine a unique channel associated with other electronic devices in the ad hoc network 1000. In particular, each electronic device included in the ad hoc network 1000 can receive signals on a common channel (not shown in FIG. 10 or FIG. 11). Using a common channel, any electronic device in the ad hoc network 1000 (or an electronic device that has not yet joined the ad hoc network 1000) responds to any recipient electronic device in the ad hoc network 1000. Broadcast a request to respond by sending a channel identifier associated with the unique channel received by the electronic device. Each response to a broadcast request can be transmitted by a respective electronic device on a common channel so that the electronic device that broadcast the request can receive the response.

  FIG. 12 is a schematic diagram of an exemplary structure of data communication by an electronic device according to an embodiment of the present invention. In particular, the first part of the data transmission includes an identifier that identifies the data source within the ad hoc network. For example, referring to FIG. 12, if the first electronic device 1005 (ie, the source) transmits data to the second electronic device 1010, the first portion of the data transmission corresponds to the first electronic device 1005. And therefore includes an identifier identifying channel 1030.

  The remainder of the data transmission includes data related to some function performed within the ad hoc network 1000, such as voice and / or data related to wireless communications. For example, the remaining portion can include data requested by the electronic device 1010. Accordingly, the second electronic device 1010 can provide a response to the transmission from the electronic device 1005 using the source identifier (ie, identifier 1030) contained in the data. As a result, the second electronic device 1010 responds by sending data on the channel 1030 for the first electronic device 1005 to receive the response.

  FIG. 13 is a diagram illustrating the operation of an embodiment of the present invention in which an electronic device broadcasts a request for a channel identifier associated with a receiver. Referring to FIG. 13, the electronic device broadcasts a request for a channel identifier associated with another electronic device that can receive the request (block 1305). As noted above, the request can be broadcast over a common channel that can be configured to allow all other suitable electronic devices to receive data within the ad hoc network of the present invention. Embodiments of the electronic device of the present invention can periodically broadcast a request for a channel identifier or broadcast a request based on external factors. Any receiver within range of the electronic device that broadcasts the request receives the broadcast request for the respective channel identifier on the common channel (block 1310). The electronic device that broadcast the request may receive a response from the electronic device that includes the respective channel identifier on the common channel (block 1315). Alternatively, the device responding to the request responds to the request using the source identifier included in the request. The electronic device that broadcast the request may send data to each of the respective electronic devices using the received identifier, if desired (block 1325).

  As described above, transmitters and receivers within the ad hoc network (or multiple access system) of the present invention can receive data on a unique channel within the ad hoc network (or multiple access system). In another embodiment of the present invention, the unique channel can be provided using, for example, an offset within a multiple access system. In particular, a unique channel of frequency and / or time can be used to provide a unique channel for communicating transmit and receive circuits.

  In addition, a unique channel within the multiple access system (and ad hoc network) of the present invention is used to modulate a reference signal (such as a spreading code) for modulating an information signal (such as voice or data provided by a user) Can be transmitted together with the information signal. By transmitting the reference signal as a component of the transmitted signal and the modulated information signal, the receiver can decode (eg, despread and demodulate) the information signal by applying the same offset that the transmitter used. it can. The receiver can despread the composite signal including the received signal implicitly using the reference signal. For example, the spreading code can be shifted by a frequency offset and combined with the information signal to provide a composite signal that can be transmitted to the receiver. The receiver can despread and demodulate the information signal by shifting the composite signal (with a frequency offset) and demodulating the received composite signal with a shifted version of the composite signal.

  In some embodiments of the present invention, different portions of the information signal transmitted to the receiver can be spread using different types of reference signals. For example, as detailed above, the first part of the information signal (or data) such as the preamble of the data packet is the modulated information signal (ie, the information signal modulated with the spreading code) and the spreading code component Itself (ie, the transmitted reference signal). A second part of the information signal, such as the payload of the data transmission, is spread using a locally generated spreading code (ie, generated at the transmitter) and locally generated corresponding to the spreading code generated locally at the transmitter Despread at the receiver using a reference signal (ie, generated at the receiver). Thus, the locally generated reference signal provides higher performance (eg, a lower bit error rate that can be provided using the transmitted reference signal) than the transmitted reference signal. Further, the first portion of the information signal can include seed information that indicates a starting point for generating a second spreading code to the second portion for data transmission.

FIG. 14 is a schematic diagram illustrating an embodiment of a transmission and reception circuit of the present invention. In particular, transmitters 1405A-1405C transmit to receivers 1410A-C in multiple-access system 1400 using their unique frequency offset). For example, the receiver 1410A determines the _first frequency offset) ω1 that any transmitter 1405A-C uses to transmit data thereto. First transmitter 1405A transmits the data to the first receiver 1410A using a unique frequency offset) omega _1. Similarly, the second receiver 1410B determines a _second unique frequency offset) ω ₂ that the transmitters 1405A-C use to transmit data thereto. The third receiver 1410C determines another unique frequency offset) ω _N that the transmitters 1405A-C use to transmit data there.

Using a unique frequency offset (ω), each receiver demodulates only the data transmitted using the corresponding frequency offset. For example, the first transmitter 1405A needs to receive using the frequency offset) ω ₁ and, as a result, transmit to the first receiver 1410A using ω ₁ as the value of the frequency offset) ω _x. . Similarly, the second transmitter 1405B transmits to the first receiver 1410A using ω ₁ as the value of the frequency offset) ω _y . Finally, the third transmitter 1405C transmits to the first receiver 1410A using ω ₁ as the value of the frequency offset) ω _z . In addition, transmitters 1405A-C similarly transmit to these receivers using the frequency offsets determined by second and third receivers 1410B-C. As a result, the transmitter can communicate simultaneously with any receiver in the multiple access system 1400 using different frequency offsets determined by the receiver.

  FIG. 15 is a schematic diagram showing an embodiment of a transmission circuit 1500 included in the electronic device of the present invention. As shown in FIG. 15, a multiplier (or modulation circuit) 1505 is provided with a reference signal (or spreading code) r (t) together with an information signal b (t) (such as data or voice provided by a user). As a result, a modulated information signal is output. The modulated information signal provided by multiplier 1505 is a component of the composite signal transmitted by transmission circuit 1500. The multiplier 1510 is also provided with a reference signal along with a frequency offset) ω. As a result, a reference signal (frequency offset) ω shifted relative to the reference signal is provided. The reference signal is shifted by ω) with respect to the modulated information signal. This is shown in FIG. 34A.

  The shifted reference signal output is also a component of the composite signal transmitted by the transmission circuit 1500. The modulated information signal and the shifted reference signal are provided to an adder circuit 1515 that combines the components (ie, the shifted reference signal and the modulated information signal). As a result, an output transmitted as a composite signal by the transmission circuit 1500 is obtained.

  According to FIG. 15, the shifted reference signal is included in the composite signal transmitted by the transmission circuit 1500. Thus, a receiver that applies the same frequency offset shifts the received composite signal to provide a shifted composite signal for despreading / demodulating the received composite signal, thereby enabling the transmitter to target An information signal demodulated by the receiver is provided. It will be appreciated that the above process can be applied by any transmitter and receiver. For example, an information signal can be transmitted from another transmitter to the same receiver using an offset frequency determined by the receiver. Furthermore, the transmitter can transmit to each of the other receivers of the present invention by shifting each reference signal by a frequency offset determined by the receiver to which the information is transmitted.

  FIG. 16 is a schematic diagram illustrating an embodiment of a receiver circuit 1600 in an electronic device of the present invention. In particular, a composite signal transmitted by transmission circuit 1500 is received and provided to first multiplier 1605 and second multiplier 1610. The first multiplier 1605 shifts the composite signal by frequency so that the shifted reference signal component included in the composite signal matches the demodulated information component in the original composite signal in frequency. The received signal is multiplied by a local signal cos () ωt + v) having a relatively small offset frequency. Therefore, the receiving circuit can avoid the use of a relatively high power RF frequency synthesis circuit.

  As described above, the shifted composite signal is shifted by ω with respect to the composite signal u (t) in the receiving circuit shown in FIG. 34B. Therefore, the component of the composite signal representing the shifted reference signal component u (t) in the receiving circuit can be matched with the information signal component included in the shifted composite signal, as shown in FIG. 34C.

  The two matching components are correlated, and the second multiplier 1610 and the low pass filter 1620 generate the information signal transmitted by the transmitter circuit 1500. The information signal can be provided using a low pass filter to provide the detection signal y (t). In other words, the second multiplier 1610 provides a signal having several components of different frequencies and direct current. The low-pass filter is provided by the second multiplier 1610. The non-DC component of the signal is removed and the DC component is passed. It will be appreciated that the direct current component provided by the low pass filter includes a detected version of the information signal transmitted to the receiver.

Still referring to FIGS. 15 and 16, the reference signal has a (pseudo) random noise characteristic. In particular, the reference signal r (t) may be a spread code symbol or a pseudo-random sequence of chips {-1, 1}. Alternatively, r (t) may be a pure noise signal n (t). In some embodiments of the present invention, r (t) is a binary signal having a constant power that can be derived, for example, by limiting the noise signal with hardware. The user information signal b (t) may be a bipolar bit stream of symbols {-1, 1}, but other signal formats may be used. Usually, the bandwidth of the information signal b (t) is smaller than the bandwidth of the reference sequence r (t). In some embodiments of the present invention, the power of the reference signal r (t) averaged over a period corresponding to the information period of b (t) is substantially constant, providing a substantially constant energy of the information bit _Eb. .

  As described above, the reference signal r (t) is used as a spreading sequence for spreading the user information signal. The information sequence signal after the reference signal is applied is expressed as s (t) = b (t) × r (t). As shown in FIG. 15, the reference signal r (t) is shifted to a higher (or lower) frequency) ω and added to the modulated signal s (t).

The total transmission signal u (t) is as follows.

となる。 The frequency offset is relative. In other words, in some embodiments, s (t) can be shifted by) ω and added to r (t). as a result,

It becomes.

As shown in FIG. 16, the composite signal (u (t)) is multiplied by cos (Δωt) in the receiver 1600 so that the frequency of the composite signal is the same amount as that of the reference signal component in the transmission circuit 1500. Only shifted and provides a shifted composite signal. The shifted composite signal is multiplied within 1610 by the received composite signal to modulate / despread the composite signal.

As a result, four frequency components of the signal v (t) are provided.

Only the DC term remains after passing through the low-pass filter (ie, b (t) r ² (t)). r ² (t) is a narrowband signal compared to the wideband signal r (t). When r (t) is a binary signal, r ² (t) is a constant. When b (t) is also a binary signal, the signal Δω is a spike signal in the frequency domain and can be removed using a filter. In some embodiments of the invention, Δω is greater than the Nyquist bandwidth of the information signal b (t). By expanding the bandwidth of r (t), the spreading factor increases and an extra-large processing gain (ULPG) can be provided in the receiving circuit 1600. Furthermore, since the interference signal is embedded in the reception signal, synchronization of the local reference signal is unnecessary in the reception circuit 1600, and a long acquisition delay can be avoided. Interfering signals that do not apply the offset used by the receiving circuit (or have no offset at all) are shifted from the information signal in the DC component. Thus, the interference signal can be filtered by the low pass filter 1620.

FIG. 17 is a schematic diagram showing a transmission circuit 1700 of the present invention. As shown in FIG. 17, the reference signal is upconverted using the carrier frequency ω _RF and shifted by a frequency offset (as disclosed with respect to FIG. 15) to provide the upconverted shifted reference signal component. . The modulated information signal (ie, the information signal spread by the reference signal) is also upconverted using the carrier frequency ω _RF to provide the upconverted modulated information signal component. The upconverted modulated information signal component is combined with the upconverted shifted reference signal component to provide a composite signal. In some embodiments of the invention, the upconverter carrier frequency is approximately 2.4 GHz. Other carrier frequencies can also be used. It will be appreciated that in some embodiments of the invention, upconversion is performed after the modulated information signal component is combined with the shifted reference signal component.

Within the receiving circuit, only the offset Δω needs to be provided. Therefore, the signal transmitted by the transmission circuit 1700 can be received using the same receiver structure as that shown in FIG. The provided frequency component is expressed as follows.

In the above embodiment, there may be components of about 2ω _RF , but these components can be ignored because they can be removed by a low pass filter in the receiver. As will be apparent to those skilled in the art, the value of ω _RF is not critical to the operation of the receiver, as shown in equations (8)-(10). In some embodiments of the present invention, the transmitted signal can be switched to any frequency by varying ω _RF over a range of discrete hopping carriers, or by performing continuous sweeps up and down. The receiver circuit 1600 need not be synchronized to transmitter hopping and sweeping as long as each component in the transmitted signal maintains a fixed frequency offset of Δω. In some embodiments of the invention, the carrier frequency ω _RF for upconverting the modulated information signal and the shifted reference signal may vary over time depending on the hopping sequence known to the receiver. .

  In some embodiments of the invention, there may be an unknown phase difference ψ between the receiver and transmitter oscillators. The phase difference ψ can be expressed as the cos (ψ) coefficient of the information signal. The phase difference ψ can be dealt with by applying the complex receiver shown in FIG. 18 in which the I and Q components are generated by applying quadrature mixing.

  In some embodiments of the invention, the frequency offset is much smaller than the bandwidth of the reference (or spread) signal. Therefore, the modulated information signal and the component of the shifted reference signal may be superimposed as shown in FIG. 19, for example.

  FIG. 20 is a schematic diagram showing an embodiment of the transmission and reception circuit of the present invention. In particular, the transmission circuits in FIG. 20 all spread the information signals generated by different transmitters using the same reference signal r (t). In addition, the transmitter applies different frequency offsets and transmits to different receivers. The outputs of the different transmitters shown in FIG. 20 can be further combined to provide a combined composite signal that can be transmitted with a single antenna. It will be appreciated that the transmitter shown in FIG. 20 may be included within a single device.

The receiver circuit uses each multiplier circuit to shift the composite signal by the respective frequency offset of the receiver. As described above, the shifted composite signal is multiplied by the received composite signal to despread / demodulate the signal. The output of the multiplier is processed by a low-pass filter to remove the DC component and provide the received information signal of each receiver. Alternatively, as shown in FIG. 21, each transmitter circuit can provide a separate reference signal r _n (t).

  The received signal mixing shown in FIGS. 20 and 21 can generate large harmonics in the output. In some embodiments of the present invention, some of the harmonics can be more easily removed using a binary reference sequence. This is because the square of these signals generates a narrowband carrier (ie, a spike wave in the frequency domain). These harmonics can then be easily removed by a broadband filter with nulls in place. In some embodiments of the present invention, the harmonics can be removed by an image rejection receiver such as the quadrature mixer shown in FIGS. In particular, in FIG. 22, a conventional image rejection mixer can be used when shifting the received signal. As shown in FIG. 23, any phase uncertainty can be resolved using a complex receiver with an image rejection function.

In another embodiment of the present invention, a unique channel can be provided within an ad hoc and multiple access system using the time offset shown in FIG. According to FIG. 24, each receiver defines a time offset τ for the transmitter to apply at the time of transmission and transmit data to any receiver. It will be appreciated that a delay can be provided to the reference signal component or the information signal. In particular, each of transmitters 2405A-2405C may transmit to a different receiver 2415A-C in multiple access system 2400 using a respective time offset τ. For example, receiver 2415A determines a _first time offset τ ₁ for any transmitter 2405A-C to transmit data thereto. The first transmitter 2405A transmits data to the first receiver 2415A using a unique time offset τ ₁ . Similarly, the second receiver 2415B determines a _second unique time offset τ ₂ for any transmitter 2405A-C to transmit data thereto, and the third receiver 2415C receives any transmission. Machines 2405A-C determine another unique time offset τ _N for transmitting data thereto. It will be understood that the terms τ and Δτ are used interchangeably herein and refer to the same time offset shown in the drawings and their description.

By using a unique time offset τ, each receiver demodulates only the data transmitted with the corresponding time offset. For example, the receiver 2415A receives with a time offset τ ₁ , and thus the first transmitter 2405A needs to use τ ₁ as the value of the time offset τ _x to transmit to the first receiver 2415A. . Similarly, the second transmitter 1405B uses τ ₁ as the value of the time offset τ _y to transmit to the first receiver 2415A. Finally, the third transmitter 2405C uses τ ₁ as the value of the time offset τ _z to transmit to the first receiver 2415A. In addition, transmitters 2405A-C similarly transmit to those receivers using the time offsets determined by second and third receivers 2415B-C. Thus, the transmitter can communicate simultaneously with any receiver in the multiple access system 2400 with a different time offset determined by each receiver.

  In another embodiment of the invention, the time offset can be used in a transmitter circuit and a receiver circuit that transmit and receive a composite signal that includes both an information signal and a reference signal. The time offset is used to delay either the information signal modulated before transmission or the reference signal.

  FIG. 25 is a schematic diagram showing an embodiment of a transmission circuit and a reception circuit of the present invention. In particular, the information signal b (t) 2505 is provided to a multiplier 2510 in the transmission circuit 2500. A reference signal r (t) is also provided to multiplier 2510, which outputs a modulated information signal that is delayed using time offset 2520 and provides a delay modulated information signal. The reference signal r (t) is added to the delay modulated information signal by an adder 2525 to provide a composite signal for transmission. It will be appreciated that the transmitted composite signal includes a reference signal component r (t) and a delay modulated information component.

According to FIG. 25, the modulated information signal s (t) is delayed by a delay 2520 and then added to the reference r (t). The transmission composite signal u (t) is expressed by the following equation.

At the receiver circuit 2550, the composite signal u (t) is provided with a delay determined by the respective receiver (and thus applied by the transmitter to transmit to a particular receiver). Multiplied by the delayed version (using multiplier 2530).

The low pass filter 2535 for filtering the output v (t) is the only term to be diffused, the output b (t−τ) r (t−τ) r (t−τ) = b (t−τ). I will provide a. Instead of delaying s (t) and adding it to r (t), delaying r (t) and adding it to s (t), u (t) = b (t) r (t) + r It will be appreciated that providing (t−τ) provides the same result. The autocorrelation and delay 2520 of r (t) can be selected appropriately to remove other term interference. For example, r (t) is a super-large spreading sequence that can provide a super-large processing gain in the receiver. Furthermore, since the reference is embedded in the received signal, synchronization of the local reference signal is unnecessary and long acquisition delays can be avoided.

  In some embodiments of the present invention, up-conversion to RF is performed separately (before synthesis to provide a composite signal) for the modulated information signal and spreading code component shown in FIG. 25 or with reference to FIG. This can be done after each component has been synthesized in a manner similar to the description.

  ULPG systems can have a large transmission bandwidth. For example, if the information bandwidth is 1 MHz and a processing gain of 30 dB is desired, the transmission bandwidth is 1 GHz (ie, ultra wideband (UWB) transmission). The signal power can be spread over a very large band, resulting in a very small spectral density (in W / Hz).

FIG. 26 is a schematic diagram illustrating an embodiment of a transmission circuit applying ULPG and a noise source. Prior to transmission, u (t) can be multiplied by an arbitrary signal q (t) when q (t) q (t-τ) = 1. For example, the transmitted signal can be upconverted to a dedicated RF frequency ω _RF that varies with time according to a frequency hopping schedule. It will be appreciated that the use of a local oscillator or synthesizer in the receiver of FIG. 26 can be avoided. The use of a steep bandpass filter can also be avoided. Thus, demodulation can be performed directly in the radio frequency domain (ie, no down conversion step is required). It will be appreciated that the same receiver shown in FIG. 25 can be used as the receiver of FIG. In some embodiments of the invention, the carrier can hop from one frequency to another, and the receiver does not need to demodulate the signal according to the hopping order used by the transmitter. When u (t) is multiplied by the carrier wave q (t) = cos (ωt), it is necessary to adjust τ and ω so that q (t) q (t−τ) = 1. In performing FIG. 26, such adjustment is ω = nx2π / τ, where n is an integer, and then 2cos (ωt) cos (ω (t−τ)) = 1 (where the 2ω term is filtered) Provided by so can be ignored). In some embodiments of the present invention, a complex receiver as shown in FIG. 27 without ω constraints is provided.

  Narrowband interference signals are also shifted and multiplied. As a result, narrow-band interference with a DC component occurs. There are several ways to remove this disturbing DC signal from the baseband signal. In one embodiment, Manchester signaling is applied in the user signal b (t). As a result, the baseband signal may not be centered on the DC component, and the DC signal can be filtered. Or, for example, J. C. Haartsen and P.M. W. Dent's “Method and Apparatus for Detection of Binary Information in the Presence of Offset, United States Patent No. 3, patented as US Patent No. 3, United States Patent No. 56” In addition, a DC removal algorithm is applied. The disclosure of which is incorporated herein by reference in its entirety.

  In some embodiments of the present invention, the first receiver can support a second, higher power receiver, and the first receiver scans the channel continuously (or frequently) for data. This data is detected and processed by a second higher power receiver. If there is no combiner in the first receiver, the first receiver can continuously scan the channel defined by τ or Δω, so that the combination of the first and second receivers is relatively small It can operate using current. For example, in some embodiments of the present invention, a first receiver is used to “wake up” a second higher power receiver, where the second receiver is the first lower power receiver. Controls operation and establishes connection after being woken up by. In other words, the first receiver can provide a low power sleep mode that scans for data on the channel, and the second receiver operates in response to detecting data to be processed by the first receiver. Can provide a high performance receiver. When the first receiver detects data to be processed, an instruction to start operation is provided to the second receiver. When the second receiver begins operation, the first receiver can pause operation until, for example, the second receiver completes operation. In some embodiments of the present invention, this type of implementation can be used in radio frequency identification (RFID) label applications including high power interrogators and low power labels.

The time offset method described above can be applied to a multi-user environment as shown in FIGS. 28 and 29, for example. The information signal from user 1 is spread using r (t) and delayed by τ ₁ , the information signal from user 2 is spread using r (t) and delayed by τ ₂ , and so on. . In other words, the reference signal is common to all channels. The reference signal r (t) is selected to have excellent autocorrelation characteristics. In FIG. 28, the outputs of the different transmitters are combined to provide a combined composite signal that is transmitted on the single antenna shown. In some embodiments of the invention, the single device for transmitting the combined composite signal is a base station. The receiver applies the respective delay of the receiver to process the combined composite signal. When any part of the combined signal is transmitted using the delay of a particular receiver, the receiver can receive that corresponding part of the combined composite signal.

In FIG. 29, the reference signal r (t) is added to each signal separately. All units may have the same r (t), or each may have its own r _i (t). The power level of the added reference signal may be lower than the power level of the spread information carrier signal (ie weighting can be applied).

FIG. 30 is a block diagram illustrating an embodiment of a transmitter and receiver of the present invention. As shown in FIG. 30, transmitters 3005A to 3005C apply differential modulation to information signals b _i (k) associated with each of the respective transmitters 3005A to 3005C. In particular, each transmitter 3005A-3005C includes a chip sequence generation circuit configured to provide a chip sequence for transmission in response to data contained in the information signal b _i (k). As the data in the information signal changes, transmitters 3005A-3005C can signal the corresponding first or second chip sequence. In some embodiments of the present invention, the first and second chip sequences are a chip sequence c and an inverted chip sequence c that is an inverted version of the chip sequence c . In some embodiments of the invention, the chip sequence c is a wideband chip sequence of length L using the alphabet {-1, 1}. The inverted chip sequence c can be obtained from the original chip sequence by replacing all 1's with -1 and all -1's with 1.

  In some embodiments of the present invention, the differential modulation provided by the transmitter is such that when the data contained in the information signal b (k) is a logical “1”, the transmitted chip sequence is the first chip sequence. When the data included in the information signal b (k) is logic “0”, the chip sequence to be transmitted is maintained as the first chip sequence. The As a result, a series of chip sequences having different lengths are transmitted by differential modulation provided by the transmitter.

Each receiver is configured to receive using a unique chip sequence length. Thus, the transmitter can communicate with different receivers using different chip sequences having different lengths with different offsets. Thus, a differential chip sequence and its different lengths are used by different transmitters to provide a differentially modulated information signal that is uniquely time offset depending on which receiver receives the transmitted data Can do. For example, when the information signal includes a logic "1", which chip sequence depending on whether the transmitting currently, the transmitter changes the c chip sequence from c to be transmitted, or from c to c (In other words, the position of the switch in FIG. 30 is changed). Alternatively, when the information signal contains a logic “0”, the transmitter continues to transmit the chip sequence c or c , depending on which chip sequence is currently being transmitted (ie, FIG. 30). The switch is in the same position). In other words, when the information signal includes a logic “1”, the chip sequence is switched, but when the information signal includes a logic “0”, the chip sequence is maintained. For example, differential modulation applied (user) bit series 1001101001 can be transmitted as c ccc c cc ccc c or c ccc c cc ccc c.

The signal is demodulated by delaying the received signal by the length L of the sequence c and multiplying the delayed version by the current version. By selecting different L for each receiver, different users can use the same medium. The length L is the length of the spreading code expressed by the number of chips, and is mapped to the delay τ together with the spreading chip speeds R _c and L and expressed as τ = L / R _c The channels differ by having different code lengths L _i , where L _i is the only parameter known to both the communicating transmitter and receiver. It will be appreciated that the chip sequence must be selected to have at least pseudo-random characteristics.

The receiver for the above system is the same as that shown in FIG. 25, FIG. 28, and / or FIG. For example, referring to the receiver embodiment shown in FIG. 25, chip sequence c or c is received by the receiver and delayed by τ (ie, the length of chip sequence c). The delayed received chip sequence is multiplied with the received chip sequence, and if the delayed received chip sequence is the same as the received chip sequence, a result of “0” is generated. Conversely, if the delayed received chip sequence is opposite to the received chip sequence, the generated result is “1”. If the accuracy of τ is not high, there may be a relatively high frequency component, which can be filtered with an LP filter.

Thus, a receiver applying a delay equal to the length L of the transmit chip sequence can receive the data. If the destination receiver detects the same (c, c or c 1 , c 2) two consecutive chip sequences, a logic “0” is implied as the modulated data. On the other hand, if the destination receiver detects two opposite ( c , c or c, c ) two consecutive chip sequences, a logic "1" is implied as the modulated data.

  In the system shown in FIG. 30, since the lengths L defined by different receivers are not equal as shown in FIG. 31, the transmitted signals may drift with each other over time. When a code is selected randomly, as in the case of an ad hoc system where no coordination between the transceivers is performed, the probability that the selected code has a low correlation characteristic is high. However, since the transmitted signals drift with each other, averaging proceeds and the system generally functions correctly. This is in contrast to systems where the transmitted signal does not drift and the worst case alignment of spreading codes must be considered. As in the broadband system, the longer the code, the more statistical averaging is performed.

In another embodiment of the invention, the sequence c (and c 1 ) can be altered to increase randomness. For example, the sign may be changed when the nature of the transmission is “burst”, during transmission or each time a new packet transmission is performed.

FIG. 32 illustrates transmission of a data stream according to an embodiment of the present invention. In particular, user information is segmented into groups of L information bits. This group is transmitted N times at a high bit rate _Rb . Therefore, each segment is compressed in time and transmitted repeatedly. At the receiver, the repeatedly transmitted group is accumulated with a delay of L / R _b during the window N _x L / R _b . After this window, the signal is sampled and a new accumulation period begins.

A scrambling code can be applied to the information signal (before segmentation) to provide pseudo-random characteristics. As shown in FIG. 32, the information signal is segmented into groups s1, s2, etc. each including L bits. These groups are transmitted N times. As shown in FIG. 33, the receiver can search for signals using delay portions each having an L-bit delay. For multi-user systems, each receiver i can have a specific L _i bits per group. By repeatedly receiving and storing the sequence, the energy of the signal accumulates. Instead of accumulating the energy of the signal by accumulating the chip as in DSSS (Direct Sequence Spread Spectrum), here the processing is performed by accumulating the information bits (spread in time) itself. The number of repetitions corresponds to the processing gain (so that the number of chips in the DS code represents the processing gain of the DSSS system). When the transmitter receives an acknowledgment from the receiver, the transmitter can stop the repeated transmission. In this way, only the minimum required energy for successful transmission is applied. A training or synchronization sequence at the start of each segment is necessary to correctly decode the segment after the accumulation is complete.

  As described above, embodiments of the present invention can provide methods, electronic devices, systems, and computer program products for communicating within a wireless ad hoc network and multiple access system (such as a mobile radiotelephone communication system). it can. For example, in some embodiments of the present invention, a transmitter transmits data to a first receiver in an ad hoc wireless network (or multiple access system) over a first channel, and the first channel Data can be transmitted to a second receiver in the ad hoc wireless network (or multiple access system) on a second channel different from. Here, the first and second channels are determined by receivers that receive the first and second transmission data, respectively. Thus, communication between a transmitter and various receivers in an ad hoc wireless network (or multiple access system) can be performed simultaneously.

  Different channels for receivers in an ad hoc wireless network (or multiple access system) can be provided by different offsets. For example, in some embodiments of the present invention, a first receiver in an ad hoc wireless network (or multiple access system) transmits data to the receiver on a first channel designated as a first offset. And the second receiver specifies a second identifier for transmitting data to the receiver on a second channel specified as a second offset different from the first offset . Accordingly, the transmitter can communicate with the first receiver by transmitting using the first offset, and can communicate with the second receiver by transmitting using the second offset. Furthermore, the transmission to the second receiver is not demodulated by the first receiver, since the first and second offsets provide different channels on which communications can be performed.

In some embodiments of the invention, the offset is a frequency offset) ω. For example, a first receiver in an ad hoc wireless network (or multiple access system) can specify a _first frequency offset (ω ₁ ) used by a transmitter attempting to transmit data to the first receiver. A second receiver in the ad hoc wireless network (or multiple access system) can specify a _second frequency offset) ω ₂ that provides data to the second receiver. Thus, the transmitter can transmit to the first receiver using the _first frequency offset) ω ₁ and can transmit to the second receiver using the _second frequency offset) ω ₂ .

In yet another embodiment of the invention, the offset is a time offset) τ. Thus, the first receiver can define the first channel as a first time offset) τ ₁ and the second receiver can designate the second channel as a second time offset) τ ₂ . As a result, the transmitter using the first time offset) tau ₁ be sent to the first receiver can be transmitted to the second receiver using the second time offset) tau _2.

  In yet another embodiment of the invention, a reference signal (or spreading code) for spreading the transmitted information signal is transmitted to the receiver as a component of the composite signal to be transmitted. The receiver can despread the received signal implicitly using the reference signal contained in the composite signal. No knowledge of the reference signal is necessary on the receiver side. Thus, embodiments of the present invention can use essentially (or effectively) random and very long reference signals as spreading codes. The random nature of the reference signal and its length provide a very low correlation. Thus, the large spread provided by the reference signal generally provides a “super extra processing gain” for the received signal. Furthermore, since the reference signal is transmitted with the data, the receiver can quickly despread the received signal.

  The disclosure of the present invention allows various changes and modifications to those skilled in the art without departing from the spirit and scope of the invention. Accordingly, it is to be understood that the illustrated embodiments are exemplary and not limiting of the invention, unlike the contents of the following claims. Thus, the following claims should be read to include not only combinations of elements of the lexical terms themselves, but also all equivalents that perform substantially the same function in substantially the same way to achieve substantially the same result. Therefore, the claims should be construed to include the specific illustrations and explanations described above, conceptually equivalent contents, and contents including the essential idea of the present invention.

It is the schematic which shows the conventional communication system. It is the schematic which shows the radio | wireless extension function of the conventional communication system. It is the schematic which shows the conventional FDMA system. 1 is a schematic diagram illustrating a conventional TDMA system. 1 is a schematic diagram illustrating a conventional direct sequence CDMA system. FIG. It is the schematic which shows the conventional FH-CDMA system. FIG. 6B is a schematic diagram illustrating frequency hopping as a function of time in the conventional FH-CDMA system shown in FIG. 6A. It is the schematic which shows the conventional ad hoc network. 1 is a schematic diagram showing a network topology of a conventional ad hoc system known as Bluetooth. FIG. FIG. 2 is a schematic diagram illustrating a perspective problem and a hidden node problem associated with a conventional ad hoc network. FIG. 2 is a schematic diagram illustrating a perspective problem and a hidden node problem associated with a conventional ad hoc network. It is a block diagram which shows embodiment of the electronic device of this invention. It is the schematic which shows operation | movement of embodiment of this invention. It is the schematic which shows embodiment of the data transmission structure of this invention. It is a flowchart which shows operation | movement of embodiment of this invention. It is the schematic which shows embodiment of the transmission circuit and reception circuit of this invention. It is the schematic which shows embodiment of the transmission circuit and reception circuit of this invention. It is the schematic which shows embodiment of the transmission circuit and reception circuit of this invention. It is the schematic which shows embodiment of the transmission circuit and reception circuit of this invention. It is the schematic which shows embodiment of the transmission circuit and reception circuit of this invention. It is a graph which shows each bandwidth of the component of the composite signal of this invention. It is the schematic which shows embodiment of the transmission circuit and reception circuit of this invention. It is the schematic which shows embodiment of the transmission circuit and reception circuit of this invention. It is the schematic which shows embodiment of the transmission circuit and reception circuit of this invention. It is the schematic which shows embodiment of the transmission circuit and reception circuit of this invention. It is the schematic which shows embodiment of the transmission circuit and reception circuit of this invention. It is the schematic which shows embodiment of the transmission circuit and reception circuit of this invention. It is the schematic which shows embodiment of the transmission circuit and reception circuit of this invention. It is the schematic which shows embodiment of the transmission circuit and reception circuit of this invention. It is the schematic which shows embodiment of the transmission circuit and reception circuit of this invention. It is the schematic which shows embodiment of the transmission circuit and reception circuit of this invention. It is the schematic which shows embodiment of the transmission circuit and reception circuit of this invention. FIG. 3 is a schematic diagram illustrating an embodiment of data transmission and reception according to the present invention. FIG. 3 is a schematic diagram illustrating an embodiment of data transmission and reception according to the present invention. FIG. 3 is a schematic diagram illustrating an embodiment of data transmission and reception according to the present invention. FIG. 6 is a schematic diagram illustrating a shift of a composite signal and a correlation between the composite signal and the shifted composite signal in a receiver according to an embodiment of the present invention.

Claims (94)

A method of communicating within a wireless ad hoc network,
Transmitting data on a first channel determined by the first receiver to a first receiver included in a wireless ad hoc network;
Transmitting data on a second channel determined by the second receiver to a second receiver included in the wireless ad hoc network.   The method of claim 1, wherein the transmitting step comprises transmitting the data from a single transmitter to various receivers. The sending step comprises:
The method of claim 1 preceding the step of requesting an identifier associated with a receiver in a wireless ad hoc network.   4. The method of claim 3, further comprising receiving an identifier corresponding to the receiver on a channel determined by a transmitter that requested the channel identifier.   4. The method of claim 3, wherein the requesting step comprises transmitting a request for the identifier over a broadcast channel configured to listen to the first and second receivers. Receiving a first identifier from the first receiver on a broadcast channel;
Receiving the second identifier from the second receiver on the broadcast channel. Transmitting the data to the first receiver using the first identifier;
7. The method of claim 6, further comprising: transmitting the data to the second receiver using the second identifier.   The method of claim 1, wherein transmitting data to the first receiver further includes transmitting an identifier associated with a transmitter that transmits the data to the first receiver.   The method of claim 1, wherein the first and second channels are unique within the wireless ad hoc network.   The method of claim 1, wherein the various channels are unidirectional.   The method of claim 1, wherein the transmitting step includes transmitting data without an identifier associated with the various receivers.   2. The transmitting step includes transmitting a first spreading code together with the data to the first receiver, and transmitting a second spreading code together with the data to the second receiver. The method described in 1.   The method of claim 12, wherein at least one of the first and second spreading codes comprises a noise signal.   The method of claim 12, further comprising changing at least one of the first and second spreading codes for subsequent data transmission. Transmitting data on the first channel defined by the first receiver as a first function;
The method of claim 1, further comprising: transmitting data on the second channel defined by the second receiver as a second function.   The method of claim 15, wherein the first function includes a first offset and the second function includes a second offset.   The method of claim 16, wherein the first and second offsets include first and second frequency offsets.   The method of claim 16, wherein the first and second offsets include first and second time offsets. Transmitting a first composite signal to the first receiver on the first channel, the first composite signal comprising a first spreading code component and a first modulated information signal component; A step including:
Transmitting a second composite signal to the second receiver on the second channel, wherein the second composite signal comprises a second spreading code component and a second modulated information signal component. The method of claim 12, further comprising: Transmitting the first composite signal comprises:
Modulating an information signal with the first spreading code to provide the first modulated information signal component;
Shifting the first spreading code by a first offset determined by the first receiver to provide a first shifted spreading code component;
20. The method of claim 19, comprising combining the first modulated information signal component and the first shifted spreading code component to provide the first composite signal. Receiving the first data at the first receiver on the first channel;
The method of claim 1, further comprising: receiving the second data at the second receiver on the second channel. A system for communicating within a wireless ad hoc network,
Means for transmitting data on a first channel determined by the first receiver to a first receiver included in a wireless ad hoc network;
Means for transmitting data on a second channel determined by the second receiver to a second receiver included in a wireless ad hoc network. A computer program product that communicates within a wireless ad hoc network,
Including a computer readable medium having computer readable program code embodied therein, wherein the computer readable program product comprises:
Computer readable program code configured to transmit data on a first channel determined by the first receiver to a first receiver included in a wireless ad hoc network;
Computer readable program code configured to transmit data on a second channel determined by the second receiver to a second receiver included in the wireless ad hoc network・ Program products. An electronic device that communicates within a wireless ad hoc network,
A receiving circuit configured to receive data from a first transmitter included in a wireless ad hoc network on a channel determined by the receiving circuit, comprising: a second circuit in the wireless ad hoc network; An electronic device comprising a receiving circuit configured to receive data from a transmitter on the channel.   25. The electronic device of claim 24, wherein the channel is determined as a function of the receiver. The data received from the first transmitter includes a first composite signal including a first spreading code component and a first modulated information signal component;
25. The electronic device of claim 24, wherein the data received from the second transmitter includes a second composite signal that includes a second spreading code component and a second modulated information signal component. An electronic device that communicates within a wireless ad hoc network,
A second receiver included in the wireless ad hoc network transmits data on a first channel determined by the first receiver to a first receiver included in the wireless ad hoc network. An electronic device comprising a transmission circuit configured to transmit data on a second channel determined by the second receiver.   28. The electronic device of claim 27, further configured to request an identifier associated with the first and second receivers in the wireless ad hoc network.   28. The transmitter of claim 27, wherein the transmitter circuit is configured to transmit a first spreading code along with the data to the first receiver, and to transmit a second spreading code along with the data to the second receiver. The electronic device described.   30. The method of claim 29, wherein at least one of the first and second spreading codes comprises a noise signal.   Further configured to transmit data on the first channel defined by the receiver as a first function, the second defined by the second receiver as a second function. 28. The electronic device of claim 27, configured to transmit data on a channel.   32. The electronic device of claim 31, wherein the first and second functions include first and second frequency offsets.   32. The electronic device of claim 31, wherein the first and second functions include first and second time offsets.   The transmission circuit is further configured to transmit a first composite signal on the first channel to the first receiver, the first composite signal comprising a first spreading code component and a first modulation. Configured to transmit a second composite signal to the second receiver on the second channel, the second composite signal comprising a second spreading code component and 30. The electronic device of claim 29, comprising a second modulated information signal component. A method of communicating within a wireless ad hoc network,
Transmitting data on a first channel defined by a first time parameter determined by the first receiver to a first receiver included in a wireless ad hoc network;
Transmitting data on a second channel defined by a second time parameter determined by the second receiver to a second receiver included in a wireless ad hoc network. Transmitting data to the first receiver comprises:
36. The method of claim 35, comprising transmitting a differentially modulated information signal using a length chip sequence as a code symbol, wherein the length is defined by a time parameter. The sending step comprises:
The differential modulation is achieved by transitioning from transmitting a first chip sequence of length to transmitting a second chip sequence of length in response to a first value in the information signal. Transmitting the received information signal;
37. maintaining a transmission of either the first or second chip sequence of the length in response to a second value in the information signal. Transmitting data to the first receiver comprises:
Transmitting an information signal, wherein the information signal is segmented to include a plurality of bits provided to the transmission circuit at a first bit rate in a first time interval, the plurality of bits 36. The method of claim 35, comprising the step of transmitting a segment multiple times at a second bit rate greater than the first rate, wherein the time parameter is defined by the length of the segment.   Receiving the information signal at the first bit rate during the first time interval, wherein the segment of the plurality of bits is multiple times at a second bit rate greater than the first rate. 40. The method of claim 38, further comprising providing data received and the plurality of bits stored multiple times and transmitted to the receiver. Transmitting data to the first receiver comprises:
Transmitting a composite signal in the wireless network, the composite signal comprising a time-shifted upconverted modulated information signal component and an upconverted spreading code component; 36. The method of claim 35, comprising upconverting the upconverted modulated information signal component and the upconverted spreading code component with a carrier frequency that varies according to a frequency hopping sequence.   41. The method of claim 40, wherein the time shift to provide an upconverted modulated information signal component after the time shift defines a time parameter. The transmitting step comprises:
Modulating an information signal with the spreading code component to provide a modulated information signal;
Delaying the modulated information signal to provide a time-shifted modulated information signal;
Upconverting the time-shifted modulated information signal using the carrier frequency to provide an up-converted time-shifted modulated information signal;
Providing an up-converted spreading code component by up-converting the spreading code component using the carrier frequency;
41. The method of claim 40, further comprising combining the upconverted time shifted modulated information signal and the upconverted spreading code component to provide the composite signal.   36. The method of claim 35, further comprising receiving a signal in the wireless network at the first receiver. The receiving step comprises:
Delaying the composite signal by the time parameter to provide a time-shifted received signal;
44. The method of claim 43, further comprising: demodulating the received signal with the time-shifted received signal to provide an information signal demodulated at the receiver. An electronic device that communicates within a wireless network,
A transmission circuit configured to transmit a composite signal in a wireless network, the information including a modulated signal and an information signal component and a spread code component, wherein the spread code component is modulated by a frequency offset; An electronic device that is shifted from a signal. The transmission circuit is
A modulation circuit configured to modulate an information signal with a spreading code to provide a modulated information signal component;
An up-converter circuit configured to shift the spreading code by a frequency offset to provide a shifted spreading code component;
46. The electronic device of claim 45, further comprising a combiner circuit configured to combine the modulated information signal component and the shifted spreading code component to provide the composite signal.   46. The spread code component of claim 45, wherein the spreading code component is shifted using an offset frequency associated with a carrier frequency used to upconvert the modulated information signal component, and the carrier frequency varies according to a frequency hopping sequence. Electronic devices. The transmission circuit is
A modulation circuit configured to modulate the information signal with a spreading code to provide a baseband modulated information signal;
A first upconverter circuit configured to upconvert a spreading code using a frequency offset and the carrier frequency and provide an upconverted shifted spreading code component;
A second upconverter circuit configured to upconvert the baseband modulated information signal using the carrier frequency to provide an upconverted modulated information signal component;
48. A combiner circuit configured to combine the upconverted shifted spreading code component and the upconverted modulated information signal component to provide the composite signal. Electronic devices. The transmitting circuit transmits a first composite signal on a first channel determined by the first receiver as a first frequency offset to a first receiver included in a wireless ad hoc network. Configured as
The transmitter circuit transmits a second composite signal on a second channel determined by the second receiver as a second frequency offset to a second receiver included in the wireless ad hoc network. 46. The electronic device of claim 45 configured to: A method of communicating within a wireless network,
Transmitting a composite signal in a wireless network, the composite signal comprising a modulated information signal component and a spreading code component, wherein the spreading code component is shifted from the modulated information signal by a frequency offset Method. The sending step comprises:
Modulating an information signal with a spreading code to provide the modulated information signal component;
Shifting the spreading code by a frequency offset to provide a shifted spreading code component;
51. The method of claim 50, comprising combining the modulated information signal component and the shifted spreading code component to provide the composite signal. An electronic device that communicates within a wireless network,
A receiving circuit configured to receive a composite signal in a wireless network, the information including a modulated information signal component and a spread code component, wherein the spread code component is modulated by a frequency offset. An electronic device that is shifted from a signal. The receiving circuit is
A conversion circuit configured to shift the composite signal by the frequency offset to provide a shifted composite signal;
53. The electronic device of claim 52, comprising: a demodulation circuit configured to demodulate the composite signal with the shifted composite signal and provide an information signal demodulated by the receiver.   54. The electronic device of claim 53, further comprising a low pass filter coupled to the demodulation circuit and configured to filter a component from the demodulated information signal. The receiving circuit is
First and second conversion circuits configured to shift the composite signal by a frequency offset using a cross-phase difference of 90 degrees to provide an in-phase component and a quadrature component, respectively, of the shifted composite signal When,
The composite signal is modulated with the in-phase component and the quadrature component of the shifted composite signal, respectively, and the in-phase component of the demodulated information signal and the quadrature component of the demodulated information signal are provided by the receiver. 53. The electronic device according to claim 52, comprising: first and second demodulation circuits configured as described above. The conversion circuit is
First and second modulation circuits configured to provide in-phase and quadrature components, respectively, of the shifted composite signal;
54. The electronic device of claim 53, comprising: an image exclusion mixer comprising: a combiner circuit configured to combine the in-phase component and the quadrature component to provide the shifted composite signal.   First and second combiner circuits configured to combine the respective in-phase and quadrature components before demodulation to provide respective in-phase components and quadrature image rejection components of the shifted composite signal are further provided. 56. The electronic device according to claim 55.   51. The method of claim 50, further comprising receiving the composite signal including the modulated information signal component and the spreading code component. The receiving step comprises:
Shifting the composite signal by the frequency offset to provide a shifted composite signal;
59. Demodulating the composite signal with the shifted composite signal to provide an information signal demodulated at the receiver.   60. The method of claim 59, further comprising filtering the demodulated information signal to filter components from the demodulated information signal.   51. The method of claim 50, wherein the spreading code component is shifted using the offset frequency associated with a carrier frequency for upconverting the modulated information signal component, the carrier frequency changing according to a frequency hopping sequence. . The sending step comprises:
Modulating the information signal with a spreading code to provide a baseband modulated information signal;
Up-converting a spreading code using a frequency offset and the carrier frequency, and providing an up-converted shifted spreading code component;
Upconverting the baseband modulated information signal using the carrier frequency to provide an upconverted modulated information signal component;
62. The method of claim 61, further comprising combining the upconverted shifted spreading code component and the upconverted modulated information signal component to provide the composite signal. The transmitting step comprises:
Transmitting a first composite signal on a first channel determined by the first receiver as a first frequency offset to a first receiver included in a wireless ad hoc network;
Transmitting a second composite signal on a second channel determined by the second receiver as a second frequency offset to a second receiver included in the wireless ad hoc network. 51. The method of claim 50. An electronic device that communicates within a wireless network,
An electronic device comprising a transmitter circuit configured to transmit a differentially modulated information signal using a length chip sequence as a code symbol, the length providing a time parameter.   65. The electronic device of claim 64, wherein the time parameter is determined by a receiving circuit to which the differentially modulated information signal is transmitted.   The transmitting circuit transitions from transmitting a first chip sequence of length to transmitting a second chip sequence of length in response to a first value in the information signal; Configured to transmit the differentially modulated information signal by maintaining transmission of either the first or second chip sequence of the length in response to a second value in the information signal 65. The electronic device of claim 64.   67. The electronic device of claim 66, wherein the first or second chip sequence transitions to a third chip sequence for use in subsequent transmissions. The transmission circuit is
A first chip sequence generation circuit configured to provide a first chip sequence of the length;
And a second chip sequence generation circuit configured to provide a second chip sequence of the length, wherein the second chip sequence includes an inverted first chip sequence. 66. The electronic device according to 66.   69. The electronic device of claim 68, wherein the length of the chip sequence associated with the transmitter circuit is unique within a multiple access system. An electronic device that communicates within a wireless network,
A transmission circuit configured to transmit an information signal, wherein the information signal is segmented to include a plurality of bits provided to the transmission circuit at a first bit rate in a first time interval; The electronic device, wherein the plurality of segments of bits are transmitted multiple times at a second bit rate greater than the first rate, wherein the length of the segments provides a time parameter.   71. The electronic device of claim 70, wherein the time parameter is determined by a receiving circuit to which the information signal is transmitted. An electronic device that communicates within a wireless network,
A transmission circuit configured to transmit a composite signal in a wireless network, the composite signal comprising a time-shifted upconverted modulated information signal component and an upconverted spreading code component; An electronic device in which a time-shifted upconverted modulated information signal component and the upconverted spreading code component are upconverted using a carrier frequency. The transmission circuit is
A modulation circuit configured to modulate the information signal with the spreading code component to provide a modulated information signal;
A delay circuit configured to delay the modulated information signal to provide a time-shifted modulated information signal;
A first up-converter circuit configured to up-convert the time-shifted modulated information signal using the carrier frequency to provide an up-converted time-shifted modulated information signal;
A second up-converter circuit configured to up-convert the spreading code component using the carrier frequency to provide an up-converted spreading code component;
The combiner configured to combine the upconverted time-shifted modulated information signal and the upconverted spreading code component to provide the composite signal. Electronic devices.   The electronic device of claim 72, wherein the carrier frequency varies according to a frequency hopping sequence. An electronic device that communicates within a wireless network,
An electronic device comprising a receiving circuit configured to receive a signal on a channel defined by a time parameter by the receiver. The receiving circuit is
A delay circuit for delaying the received signal to provide a time-shifted received signal;
76. The electronic device of claim 75, comprising: a first demodulation circuit configured to demodulate the received signal with the time-shifted received signal and provide a first demodulated information signal at the receiver. device.   77. The electronic device of claim 76, further comprising a low pass filter configured to filter a component from the first demodulated information signal.   The information signal is segmented to include a plurality of bits provided at a first bit rate in a first time interval, wherein the plurality of bits segment has a second bit rate greater than the first rate. 76. The electronic device of claim 75, wherein the electronic device is received multiple times at a rate and the length of the segment provides a time parameter defined by the receiver. The receiving circuit is
A plurality of sequential delay circuits equal in number to the number of times the plurality of bit segments are received, each of the plurality of sequential delay circuits delaying its input by the time parameter to provide its output; A sequential delay circuit providing the output of
79. The electronic device of claim 78, comprising an adder circuit configured to add the plurality of outputs. The receiver is
A phase shifter for phase shifting the received signal after the time shift;
A second demodulation circuit configured to demodulate the received signal with the phase-shifted received signal shifted in phase and provide a second demodulated information signal at the receiver; 77. The electronic device of claim 76, wherein one demodulated information signal is an in-phase component of the demodulated information signal and the second demodulated information signal is a quadrature component of the demodulated information signal. A system for communicating within a wireless network,
Means for transmitting an up-converted signal that is up-converted using a carrier frequency;
Means for receiving the up-convert signal;
Means for demodulating the received up-converted signal without using a carrier frequency.   The system of claim 81, wherein the carrier frequency varies according to a frequency hopping sequence. An electronic device that communicates within a wireless network,
Receiving a composite signal including a modulated information signal component corresponding to a first portion of data communication and a spreading code component for modulating the information signal, wherein the data transmission is addressed to the electronic device; A first receiver configured to provide;
And a second receiver coupled to the first receiver and configured to initiate operation in response to the indication that the data transmission is destined for the electronic device.   84. The electronic device of claim 83, wherein the first receiver comprises a wireless identification tag receiver. An electronic device that communicates within a wireless network,
Configured to receive a composite signal including a first modulated information signal component and a first spreading code component for modulating an information signal corresponding to a first portion of data transmission; An electronic device comprising a receiver configured to receive a second modulated information signal component corresponding to a second portion of a data transmission that is modulated with a second spreading code different from the spreading code.   86. The electronic device of claim 85, wherein the first spreading code includes a transmission reference signal that transmits the first modulated information signal as part of the composite signal to the receiver.   86. The electronic device of claim 85, wherein the second spreading code is generated locally at the transmitter and includes a spreading code generated locally at the receiver.   86. The electronic device of claim 85, wherein the first portion of the data transmission further includes seed information indicating a starting point for generation of the second spreading code. An electronic device that communicates within a wireless network,
Configured to transmit a composite signal including a first modulated information signal component and a first spreading code component for modulating an information signal corresponding to a first portion of data transmission; An electronic device comprising a transmitter configured to transmit a second modulated information signal component corresponding to a second portion of a data transmission that is modulated with a second spreading code different from the spreading code. A method of communicating within a wireless network,
The first transmission circuit receives a composite signal including a modulated information signal component corresponding to a first part of data communication and a spread code component for modulating the information signal, and the data transmission is performed by the first transmission circuit. Providing a display destined for an electronic device including a receiving circuit of:
Initiating operation of a second receiving circuit coupled to the first receiving circuit in response to the indication that the data transmission is destined for the electronic device. A method of communicating within a wireless network,
Receiving a composite signal including a first modulated information signal component and a first spreading code component for modulating an information signal corresponding to a first portion of data transmission;
Receiving a second modulated information signal component corresponding to a second portion of the data transmission that is modulated with a second spreading code different from the first spreading code. A method of communicating within a wireless ad hoc network,
A method comprising transmitting data to various receivers included in a wireless ad hoc network on various channels.   The various receivers comprise at least first and second receivers, the various channels being at least a first channel from which the first receiver receives the data, and the second receiver comprising the second receiver 94. A method according to claim 92, comprising a first channel for receiving data.   94. The method of claim 93, wherein the first channel is determined by the first receiver and the second channel is determined by the second receiver.

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