1A illustrates an interface in communication with a user equipment device (UE) 102 and a wireless wide area network (WWAN) 104 when a base station 105 in a WWAN cannot recover the higher order modulation component of the layer signal 106. A block diagram of node 100 is shown. When the base station 105 in the interface WWAN is unable to recover the data 102, the wireless node 100 transmits the data 112 transmitted by the UE device 102 to the WWAN so that the wireless node 100 receives a wireless wide area network (WWAN). Help the operation of). As described in detail below, the UE device 102 transmits a hierarchical modulation signal 106 comprising a higher order modulation component 108 and a lower order modulation component 110 to one base station 105. Depending on the communication channel 114 between the UE device 102 and the base station 105, the base station 105 may not recover the higher order modulation component 108. For example, due to distance, disturbances, noise, multi-path interference or other factors, the signal-to-noise ratio of the signal may not be appropriate for reception at the base station 105. However, lower order modulation component 110 may be recoverable after signal transmission over channel 114. For example, higher order modulation is 16 quadrature amplitude modulation (QAM), lower order modulation is orthogonal phase shift modulation (QPSK), and base station 105 may be distinguished between four points in the QPSK constellation, but the QAM constellation Of the 16 points, it cannot determine which point will be sent. The communication channel 116 between the UE device 102 and the interface node 100 is of sufficient quality, and the interface node 100 can recover the higher order modulation component 108 and demodulate the signal 106. And recover the transmitted data 112 using higher order modulation. The interface node sends data 112 to the base station 105.
In some cases, the base station 105 may not be able to recover the lower order modulation component 110 or higher order modulation component 108 due to the channel 114 state. In such a case, data corresponding to two components may be sent from the interface node 100 to the WWAN 104. However, as described with respect to FIG. 1A, the state of the channel 114 allows the base station 105 to demodulate the lower order modulation component 110, but cannot demodulate the higher order modulation component 108. 1A shows the lower order modulation component 110 as a solid arrow and as a solid block, and the higher order modulation component 108 as a dashed arrow and a dotted block at the base station 105, so that the lower order modulation component 110 is It will be described that the higher order modulation component 108 can be recovered by the base station 105 and that the higher order modulation component 108 cannot be recovered by the base station 105.
The channel used to transmit data 112 from interface node 100 to base station 105 may be a wired communication channel or a wireless communication channel, and may consist of a combination of network, equipment, or device. Examples of suitable communication channels may include wired and wireless IP protocol channels including the Internet or intranet, and point-point microwave channels.
1B is a block diagram of an interface node 120 in communication with a user equipment device (UE) 122 and a wireless wide area network (WWAN) 124, to provide multiple service level communication services. The UE terminal device 122 transmits one layer signal 126 to the base station 125 and the interface node 120 in the WWAN, and at least two service levels are provided to the user for uplink communication. Can be. In an example embodiment, the first service level facilitates real-time data transmission, such as real-time voice transmission, and the second service level facilitates anti-delay data transmission, such as email and file upload. As described further below, the UE apparatus 122 includes a hierarchical modulation component 130 that includes a lower order modulation component 130 that includes first level service data and a higher order modulation component 128 that includes second level service data. Generate and send 126. Thus, in the embodiments described herein, the first level service data is real time data and the second level service is anti-delay data.
Depending on the communication channel 124 between the UE device 122 and the base station 125, the base station 125 may not recover the higher order component 128. For example, due to distance, disturbances, noise, multipath interference or other factors, the signal to noise ratio of the signal may not be appropriate for reception by the base station 125. However, lower order modulation component 130 may recover after transmission of signal 126 over channel 134. For example, higher order modulation is 16 quadrature amplitude modulation (QAM) and lower order modulation is quadrature phase shift keying (QPSK), and the base station 125 may be distinguished between four points in the QPSK nebula, but the QAM nebula 16 points Chinese cannot determine whether a point will be sent. The communication channel 136 between the UE device 122 and the interface node 120 is of sufficient quality, and the interface node 120 can recover the higher order modulation component 128 and demodulate the signal 126. It is possible to recover the transmitted data 132 using higher order modulation. The interface node sends data 132 to the recipient.
Various techniques may be used to manage communication via the interface node 120. In one embodiment, the interface node 120 transmits information related to the communication link between the UE device 122 and the interface node 120 to the device station 125. Based at least on the quality of the link, the base station 125 assigns an appropriate higher or lower modulation for the second level service data transmission. In some cases, the allocation may be based on the type and size of data, availability of communication resources, user priority level, or other factors.
In some cases, base station 125 may not be able to recover lower order modulation component 130 or higher order modulation component 128 because of channel 134 conditions. In such a situation, lower order modulation component data may be sent from the interface node 100 to the WWAN 104. However, in the situation described with respect to FIG. 1B, the channel 134 state allows the base station 125 to demodulate the lower order modulation component 110.
Also, even if the channel conditions are appropriate, the base station 125 may not demodulate higher order modulation components. 1B shows the lower order modulation component 130 as a solid arrow and as a solid block, and the higher order modulation component 128 as a dashed arrow and a dotted block at the base station 125, so that the lower order modulation component 130 is It will be explained that the higher order modulation component 128 can be recovered by the base station 125 and that it cannot be recovered by the base station 125.
Although in some cases, interface node 120 may be needed to demodulate the lower order modulation component, the interface node 120 does not demodulate the lower order modulation component in an embodiment. 1B shows the lower order modulation component 130 as a dashed arrow and a dashed block and the higher order modulation component 128 as a solid arrow and a solid line block at the interface node 120, so that the higher order modulation component 108 is shown. To be restored by the interface node 120 and that the lower order modulation component 130 cannot be recovered by the interface node 120. The channel used to transmit the second service level data 132 from the interface node 120 to the intended recipient may be a wired communication channel or a wireless communication channel and may include a network, equipment, or device combination. Can be. Examples of suitable communication channels include wired link and wireless link IP protocol channels including the Internet or intranet, and point-point microwave channels.
1A and 1B, the WWANs 104 and 124 and the UE devices 102 and 122 may be part of a wireless communication system 118 and 138 that may include any number of base stations and infrastructure. . The principles described above can be applied to any of a number of communication systems, protocols, devices and configurations. Wireless communication systems 118 and 138 are implemented in accordance with WWAN systems, such as cellular communication systems. Examples of suitable communication techniques include those operating according to code division multiple access (CDMA) standards such as cdma2000 1X, IxEV-DO, and W-CDMA. In some cases, wireless communication systems 118 and 138 may operate in conjunction with other standard technologies, such as OFDM based standards or GSM standards. The wireless communication technologies 118 and 138 are geographically distributed and include various device stations 105 and 125 to provide wireless services to the UE devices 102 and 122 within the geographic area. The interface node 100 is geographically distributed and communicates with one or more base stations via a wireless or wired channel. One base station 105, 125 may communicate with any number of interface nodes and UE devices 102, 122. In some situations, one interface node 100, 120 is implemented within a wireless local network (WLAN) access point (AP) that is part of a WLAN.
The various functions and operations of the blocks described in connection with the wireless communication systems 118, 138 may be performed regardless of the elements, circuits, or number of elements. Two or more functional blocks may be integrated into a single device, and the functions described as being performed on any single device may be implemented in multiple devices. For example, at least some of the functions of the base station 105 may be performed by a base transceiver station (BTS), a base station controller (BSC), or a mobile switching center (MSC). Also, in some circumstances, other higher or lower modulation combinations may be used. Examples of other suitable combinations may include BPSK and QPSK, QPSK and 16-QAM, 16-QAM and 64- QAM, 64-QAM and 256-QAM, and other combinations. In addition, the hierarchical modulation scheme may include two or more modulation orders. For example, BPSK may be used for lower order modulation, QPSK may be used for intermediate order modulation, and 16 QAM may be used for higher order modulation. Other combinations using phase-offset (eg offset-QPKS) are possible.
FIG. 2 is a block diagram of interface nodes 100 and 120 in communication with WWANs 104 and 124 and UE devices 102 and 122 in accordance with the embodiment shown in FIGS. 1A and 1B. The WWAN 104, 124 base station 105, 125 LJE devices, and the interface nodes 100, 120 may be implemented using hardware, software or formware. The various functions and operations described in connection with the base station 105, 125, interface nodes 100, 120, and the UE devices 102, 122 may be implemented in any number of devices, circuits, or elements. In addition, two or more functional blocks may be integrated as a single device and the functions described as being performed on a single device may be performed on multiple devices.
Each of the UE devices 102, 122 is a transmitter (TX) 210 and a receiver (RX) for communicating with at least one antenna 202, a processor 204, a memory 206, and a base station 105, 125. An air interface having a radio frequency transceiver 208 having 212. UE devices 102 and 122 with multi-mode capabilities include additional network interfaces and transceivers for communicating with WLAN access points. The processor 204 and the transceiver 210 are configured to perform hierarchical modulation and to transmit the hierarchical modulation signals 106 and 126. The processor 206 performs baseband processing on the digitized information including modulation and demodulation, encoding and decoding, interleaving and de-interleaving, multiplexing and de-multiplexing, error correction operations, and the like. Examples of suitable processors 204 include one or more digital signal processors (DSPs) and special purpose integrated circuits (ASICs). The memory 206 stores one or more software programs executed by the processor 204 to perform its functions, and stores identification, protocols, and other data related information.
With reference to FIGS. 1A and 2, the UE device 102 sends a hierarchical modulated signal 106 to a base station 05 that in this embodiment causes demodulation of at least both components 108, 110. The base station demodulates the received layer signal 106 hierarchically. In various situations, the base station 105 successfully recovers data transmitted through both components. In some circumstances, however, the channel 114 between the UE device 102 and the base station 105 does not have sufficient quality to allow the base station 105 to recover one or both of the components 108 and 110. Do not. In an embodiment, the base station 105 informs the interface node 100 which data cannot be recovered. The base station 105 notifies the interface node 100 of data that cannot be recovered by the base station 105 either directly or through the WWAN infrastructure 234 and that must be forwarded to the WWAN 104. In response, the interface node 100 forwards the appropriate data to the WWAN 104 as described in detail below. In some embodiments, higher order modulation component data may be forwarded to the WWAN 104 without receiving communication from the base station 105 or the WWAN 104.
1B and 2, the UE device 122 transmits the hierarchical modulation signal 126 to the base station 125 demodulating only the lower order modulation component 130 in an embodiment. The base station 125 hierarchically demodulates the received layer signal 126 to recover the first service level data. In an embodiment, the first service level data includes real time voice information to facilitate a two-way telephone call.
The interface node 100, 120 may include one or more WWAN receivers 214 for receiving WWAN signals from one or more UE devices 102, 122 and the network 222 for communication with the WWANs 104, 124. Include. In an embodiment, the WWAN receiver 214 is part of a WWAN transceiver 216 that includes a WWAN transmitter 218 to facilitate upward communication with the UE devices 102, 122. In some cases, the WWAN transmitter may be omitted. When the interface nodes 100, 120 are implemented as part of a WLAN access point, the access point also includes hardware and software for providing WLAN services. The interface nodes 100, 120 further include a controller 220 coupled to the WWAN interface 222 and the WWAN receiver 214. The controller 220 performs the control and other functions described herein and facilitates the overall operation of the interface nodes 100, 120. The controller 220 includes a memory 224 that includes one or more random access memory (RAM) or read only memory (ROM) memory devices.
The network interface 222 includes hardware, software, and formware combinations for transmitting higher order modulated data 112, 132 to the WWANs 104, 124. In an embodiment, one wired interface 226 is communicated via an access router 228 or an IP network 230 to an access gateway 232 in a WWAN infrastructure 234 serving the base stations 105, 125. . Wired interface 226 exchanges messages with the access router 228 and the Internet Protocol (IP) network 230. The wired interface 226 provides packet data communication and facilitates access to one access gateway 232 in the WWAN infrastructure 234 and to the Internet via the access router 228. In some cases, at least a portion of the wired interface 226 may be implemented separately from the network interface 222. The access router 228 may be connected to other interface nodes 100 and 120 or to a WLAN access point and may also provide communication management and control functions to the WLAN. In some cases, the access router 228 may be implemented within the interface nodes 100 and 120 or the WLAN access point, or may be removed. The connection between the access gateway 232 and the interface nodes 100, 120 may also include a wireless communication link such as, for example, a satellite communication link or a point-point microwave link. In addition, the interface nodes 100 and 120 may include a wireless communication link, such as a WiMax or Point-to-Point link. In such a situation, the network interface 222 includes a wireless interface transceiver 240 to communicate with the base station 105, 125, or equipment connected to the base station 105, 125. Thus, the wireless receiver may be located in the base station 105, 125 or elsewhere in the WWAN 104, 124. The air interface transceiver 240 is shown in dashed blocks in FIG. 2 to indicate that the air interface transceiver 240 is not needed when the wired interface 226 provides communication to the WWANs 104 and 124. . Accordingly, the air interface transceiver 240 may be replaced with the wired interface 226 and may be included or omitted in addition to the air interface 226.
The WWAN receiver 214 is configured to receive the hierarchical modulated signals 106, 126 from at least one UE device 102, 122. As described in connection with FIG. 1A, the hierarchical modulated signal 106 includes a lower order modulation component 110 and a higher order modulation component 108. The WWAN receiver 214 demodulates the hierarchical modulated signal 106 to recover a higher order modulated data stream, which is later modulated or processed for transmission to the base station 105. Even if the base station allows demodulation of higher order modulation components, in some cases only the lower order modulation components are recovered. Thus, in such a case, the hierarchical modulation signal 106 is the lower order modulation component 110 recoverable by the base station 104 when a WWAN hierarchical modulation signal is transmitted to the base station 104 via the communication path 114. And a higher order modulation component 108 that is not recoverable by the base station 104 after transmitting over the communication path 114. As described in connection with FIG. 1B, the hierarchical modulated signal 106 includes a lower order component 110 and a higher order modulation component 108. The WWAN receiver 214 demodulates the hierarchical modulated signal 106 to recover a higher order modulated data stream, which is later modulated or processed for transmission to the receiver. The lower order modulation component corresponds to first service level data and the higher order modulation component corresponds to second service level data.
In addition to other information, the memory 224 stores communication device identification values corresponding to each of the UE devices 102 and 122 serviced by the interface nodes 100 and 120. The communication device identification value may comprise an electronic serial number (ESN) or other unique data. The identification value may be stored at interface node 100 using various known techniques. An example of a suitable method of storing the values includes storing the values during an initialization process performed when the interface node 100 is installed or during periodic updates to the interface nodes 100, 120. In an embodiment, the identification information received from the WWAN infrastructure 234 includes an identification value identifying a local UE device 102, 122 in proximity to the interface node 100, 120. Thus, the identification information allows the interface nodes 100 and 120 to update the user list of the device to be monitored. In some implementations, identification values received from WWAN infrastructure 234 are stored in the user list. In another embodiment, the user list may include a pre-programmed identification value and an identification value combination received from the WWAN infrastructure. Such identification information may be a combination of parameters, numbers, identifiers, or information providing an interface node with appropriate data for identifying a particular UE device 102, 122.
In an embodiment, the WWAN infrastructure 234 includes a packet switch core network that includes one or more access gateways 232. Controller 236 includes a processor, computer, processor device or other processing device in which at least some of the access gateway functions may be performed by the controller 236. Such controllers include other location processors, such as location servers (PDEs) or location servers. One memory 238 includes a suitable memory device, such as RAM or ROM, that provides electronic storage of information. In addition to other types of information, the memory stores identification information and information related to the location of interface nodes 100 and 120. The access router 228 can be connected to the access gateway 232 using a combination of wired and wireless connections. Examples of suitable connections include T1 lines, fiber optic cables, coaxial cables, and point-to-point microwaves. The access gateway 232 is a communication interface that allows the interface nodes 100, 120 to communicate with the WWAN infrastructure 234. Various components and functions of the WWAN infrastructure 234 may be implemented using multiple devices spread across the core network. For example, processing functionality for determining which UE devices 102 and 122 should be monitored may be implemented in one server connected to a PDE located at different locations.
With reference to FIGS. 1A and 2, in operation, interbase node 100 monitors a reverse link WWAN channel that may include a reverse link layer modulated signal 106 transmitted from one UE device 102. The frequency is adjusted or configured such that the reverse link WWAN receiver 214 can receive the reverse link layer modulated signal 106. As described in detail below, the layer signal 106 is received and demodulated to recover the higher order modulation component 108. The recovered data stream 112 is forwarded to the base station via the network interface 222.
Many techniques can be used to manage communication via the interface node. Thus, the type, number, and size of messages for transmitting control and data signals between the interface node, the WWAN 104, and the base station 105 depend on the particular management scheme. In an embodiment, the interface node 100 transmits information related to a communication link between the UE device 102 and the interface node 100 to the base station 105. Based at least on the link quality, the base station 105 assigns the appropriate order of modulation to the UE device 102 and transmits the lower order modulated data and the higher order modulated data. In some cases, the allocation is based on the type and data size of the data, the availability of communication resources, the user priority level, or other factors. Further, depending on the quality of the channel, the base station 105 instructs the interface node to forward either higher order modulated data, both higher order modulated data and lower order modulated data, or transmits no data from the interface node to the WWAN. Do not. The indication may be valid for a fixed number of frames, time periods, sessions, or other periods.
1B and 2, during operation, the interface node 120 monitors a reverse link WWAN channel that includes a reverse link layer modulated signal 126 sent from the UE device 122. The reverse link WWAN receiver 214 is frequency tuned or configured to receive the reverse link layer modulated signal 126. In an embodiment, the base station 125 is informed about the communication link quality between the UE device 122 and the interface node. After a UE device 122 is discovered, the interface node 120 monitors the communication channel 136 and generates a channel quality indicator based on the quality. The channel quality indicator may be any one of a number of parameters or features. Examples of suitable quality indicators are received signal strength and signal to noise ratio (SNR). The channel quality indicator is forwarded to the base station 125 using information to allocate resources and assign modulation schemes and transmission schedules to the UE device 122. The resource allocation may be determined by other factors such as available capacity, bandwidth requirement of uplink transmission, and user priority.
Once the transmission schedule is established, appropriate information is sent to the interface node 120 and the UE device 122. Control techniques in accordance with known techniques are used to assign communication parameters to the UE device 122. The interface node 100 uses the information provided by the base station 105 to receive a signal transmitted from the UE device 122. As described in more detail below, the hierarchical signal 126 is received and demodulated to recover the higher order modulation component 128. The recovered data stream (second service level data) 132 is forwarded to the receiver via the network interface 222. The data 132 is routed through a network or system regardless of the number before it is received by the recipient. For example, the data 132 may include email sent to the wireless mobile device via the Internet and a WWAN system or WLAN system.
3 is a flowchart of a method performed by UE devices 102 and 122 according to an embodiment of the present invention. The method may be performed using hardware, software or software combinations in the UE devices 102 and 122, but in embodiments, the method may be performed at least partially by executing software code.
In step 302, the UE device 102, 122 receives a communication parameter from the base station 105, 125 indicating a minimum modulation order for transmission. In accordance with known control techniques, base stations 105 and 125 transmit control signals for assigning lower order modulation and higher order modulation for uplink transmissions from the UE devices 102 and 122. Other parameters such as power control level and timing information are also assigned. The assignment of the higher order modulation is in response to a request from the UE device 102, 122 for communication in addition to voice communication.
In step 304, hierarchical modulation is performed to generate the hierarchical modulated signal. The base data signal and the extended data signal are modulated and cause to generate a layer signal including data from both interleaved data signals. In the embodiment described in FIG. 1A, all of the data signals are intended to be received by the base station, but in some cases include information with different priority levels. Examples of data signals include a base station signal that includes voice information and an extended data signal that includes upstream digital data. In another embodiment, control data may be sent via the extension data signal and user data may be sent using the base data component. In accordance with the embodiment described in FIG. 1B, first level service data such as voice and second level service data such as anti-delay data are combined to form the hierarchical modulation signal 126.
In step 306, the hierarchical modulated signal is transmitted. In most cases, the communication path 114 from the UE device to the base station 105 will be different from the communication path 116 to the interface node 100.
4A is a method flow diagram performed at the interface node 100 in accordance with the embodiment of the present invention shown in FIG. 1A. The method may be performed using any combination of hardware, software, or formware in the interface node 100, although the method may be implemented at least in part by executing software code on the controller 220 in an embodiment. Is executed.
In step 402, the hierarchical modulation signal 106 is received from the UE device 102. In an embodiment, the hierarchical modulation signal 106 is a reverse link (RL) WWAN signal received via the communication path 116 from the UE device 102 to the interface node 100. The hierarchical modulation signal 106 includes a lower order modulation component 110 corresponding to a base data signal and a higher order modulation component 108 corresponding to an extension data signal.
In step 404, the higher order modulation component is demodulated. As described in more detail below, the extended data signal is recovered by performing layer demodulation, de-interleaving and decoding. In some cases, both the lower and higher order modulation components are recovered.
In step 406, a request for higher order modulation component data is received from the WWAN. In some cases, such a request includes a request for lower order modulation component data. In an embodiment, the WWAN 104 issues a request based on an indication from base station 105 that one or more components of signal 106 cannot be received. The WWAN sends the request to all interface nodes 100 in the UE device 102 area.
In some cases, step 406 may be omitted and higher order modulation components continue to recover and continue to be sent to the network. In addition, the lower order modulation can also continue to be recovered and forwarded.
In other cases, the interface node 100 may determine whether to send the lower order modulation component data or the higher order modulation component based on a certain threshold. The threshold is based on the signal-to-noise ratio (SNR) or signal strength of the signal received at the interface node, and / or the SNR or signal strength of the signal 106 received at the base station 105, for example. Information is periodically sent from the WWAN or base station to the interface node associated with the received signal 106 at base station 105.
At step 408, an extended data signal is sent. In an embodiment, the extension data signal (higher modulation component data) is sent to the WWAN 104. The extended data signal is formatted, modulated, and processed to form a signal for transmission to the WWAN 104. The signal is sent and transmitted using a number of wired or wireless technologies. In this embodiment, an extension data signal (higher modulation component data) is transmitted over a network coupled to the WWAN infrastructure 234. In some cases, the higher order modulation component data is sent directly to the intended recipient. For example, if the higher order modulation component data is an email, such email is routed directly through the IP network 230 without being sent to the WWAN infrastructure. In some cases, the extended data signal is forwarded to the base station 105. Further processing may be required to combine the extension data signal with the base station data signal. Such processing may be performed at base station 105 in the WWAN infrastructure 104 or elsewhere in the network.
4B is a flowchart of the method performed at the interface node 120 according to the embodiment of the present invention as described in FIG. 1B. Although the method may be performed using hardware, software, or formware combinations in the interface node 120, such a method may be performed at least in part by executing software code on the controller 220 in an embodiment.
At step 422, the channel quality indicator is sent to the base station 125. After the interface node 120 deletes the UE device 122, the channel 136 is monitored by evaluating the signal transmitted from the UE device 122. In an embodiment, the interface node 100 uses the information provided by the WWAN to receive and demodulate the uplink signal transmitted to the base station 125. One or more channel quality parameters, such as signal to noise ratio, signal strength, signal attenuation, or bit error rate (BER), are generated and transmitted to base station 125.
In step 424, uplink communication parameters are received from the base station 125. The uplink communication parameter provides information related to communication resource allocation to the LIE device 122 and provides at least modulation order and scheduling information allocated to the UE device 122.
At step 426, a hierarchical modulation signal 126 is received from the UE device 122. The layer modulated signal 126 is received via the communication path 136 from the UE device 122 to the interface node 120. The hierarchical modulated signal 126 includes a lower order modulation component 130 corresponding to the base station signal and a higher order modulation component 128 corresponding to the extended data signal.
In step 428, the higher order modulation component is demodulated. As described in more detail below, the extended data signal is recovered by performing layer demodulation, de-interleaving and decoding. In some cases, lower order components and higher order components are recovered.
In step 430, the second service level data (extended component) is forwarded to the receiver. In an embodiment, a communication link is established with the network and, in some cases, with the recipient's user equipment device before the extension component is forwarded. For example, if the second service level data is an email, the interface node 120 establishes a communication link with the Internet and sends the email message using an IP protocol.
The extended data signal is formatted, modulated, or processed to cause the interface node 120 to form a signal for transmission to a network or WLAN that is part of or is connected to the WLAN access point. The signal is generated and transmitted using either wired or wireless technology. In this embodiment, an extended data signal (second service level data) is transmitted via the IP network 230. In some embodiments, the extended data signal is forwarded to base station 125 or WWAN 124.
5 is a block diagram of the hierarchical modulation operation in the UE device 102, 122. The functional blocks shown in FIG. 5 are realized in embodiments by at least some of the transmitter 210, the memory 206, and the processor of the UE device 102, 122. However, various functions and operations of the blocks described in connection with FIG. 5 may be realized with devices, circuits, or elements embodied by a combination of software, hardware, or formware. Two or more functional blocks may be integrated into one device, and functions described as being performed by a single device may be realized by multiple devices.
Base data signal 500 is received at base component encoder 502 and extension data signal 504 is received at extension component encoder 506. The base data signal 500 and the extended data signal 504 include various types of data and signals. In one embodiment as shown in FIG. 1A, examples of the base data signal 500 and the extended data signal 504 include two streams, real-time and best-effort data, control and from the same data resource. Data, and voice and data signals. In the embodiment as shown in FIG. 2A, the data and signal correspond to the first service level data and the second service level data, respectively.
Continuing with reference to FIG. 5, each data signal is encoded and processed according to known techniques before the signal is interleaved by the base interleaver 508 and the extended component interleaver 510. The encoders 502, 506 and interleavers 508, 510 provide error correction processing and may use appropriate error correction coding, such as turbo coding. The interleavers 508 and 510 may use an appropriate interleaving algorithm. The encoding and interleaving techniques used by one component are different from those used by other components.
Multiplexer (MUX) 512 multiplexes the interleaved signals before layer modulator 514 modulates the multiplexed signal. The multipliers 516, 518, and 520 multiply Walsh-codes W 0 , W C with in-phase and quadrature components, and multiply the pilot signals 522 and multiply. do. Gain multipliers 524, 526, and 528 adjust the gain of each of the in-phase and quadrature phase components and the pilot signal. A time division multiplexer (TDM) 530 multiplexes the pilot, in-phase and quadrature signals to generate a hierarchical modulated signal 206 transmitted by the transmitter 210 via an antenna.
6 is a block diagram for mapping bits into layer modulation symbols. Each of the base component and extension components are individually encoded and interleaved by interleavers 508 and 510. The outputs Bi , E j are multiplexed by the multiplexer 514 to generate symbols S 0 , S 1 , S 2 , S 3 . Depending on the number of parameters that make up the base component, the multiplexing may vary. For example, instead of changing the bits from each of the components for multiplexing, each base bit is followed by three extension bits.
FIG. 7 shows a graph of an example 16-QAM constellation 700 illustrating the hierarchical modulation symbol generated by hierarchical modulator 514. In this example, each modulation symbol represents four multiplex bits (ie, S 3 , S 2 , S 1 , S 0 ). The bits multiplexed from the base component are represented by S 0 and S 2 , and the multiplexed bits from the extension component are represented by S 1 and S 3 . The modulation symbol is configured not to change within the same quadrant. Thus, the multiplexed bits from the base component are essentially QPSK modulated and the multiplexed bits from the extension component are 16-QAM modulated.
As shown in FIG. 5, the base and extension components are modulated and then transmitted with a pilot signal. The pilot gain G p is independent of the gain G b for the base and extension components. In order to improve the base component reception, the UE device 102, 122 adjusts the gain G b so that the base data signal can be successfully demodulated if the interface node 100 successfully receives the pilot signal. do.
8 is a block diagram of an exemplary WWAN receiver 214 for performing layer demodulation at the interface node 100. In addition to other components, the receiver 214 includes a receiver front end (RX FE) 801, a delay buffer 802, a wilshe-code (W 0 , W C ), and a coefficient (W * ) multiplier 804. 806, 808, 810, 812, channel estimator 814, threshold comparator 816, and layer demodulator 818. After describing the pilot using the Walsh-code (W 0 ), channel evaluation is performed to evaluate specific gravity (W * ) and SNR. The delayed data is descrambled using Walsh-code W C and then equalized using coefficients. Depending on the SNR of the current signal, QPSK or 16-QAM demodulation can be used. Receiver 214 also has a base-component de-interleaver 826 and decoder 828, and an extended component de-interleaver 822 and decoder 824. In some cases, the base de-interleaver 826 and the base decoder 828 may be omitted. At least some of the functional blocks may be implemented in the controller 220. However, various functions and tasks of the blocks described in connection with FIG. 8 may be realized with devices, circuits, or elements embodied by a combination of software, hardware, or formware. Two or more functional blocks may be integrated into one device, and the functions described as being performed in a single device may be realized in multiple devices.
The channel estimator 814 provides a signal strength indicator (C / I) to a threshold comparator 816 that determines the modulation order to be used by the hierarchical demodulator 818. The threshold comparator 816 may include one or more lookup tables (LUTs) to store signal to noise ratio (SNR) ranges and corresponding modulation order values. The LUT for the SNR may be updated according to the relative gain of the pilot gain G p and the gain used in the base component since the transmitted pilot level may change depending on traffic conditions. The LUT may also include code-rate information. If the threshold comparator 816 indicates good (below the threshold above), the base and extension components can be successfully demodulated using the 16-QAM demodulator.
However, if the threshold comparator 816 exhibits a low SNR, it is possible that only the base component can be successfully demodulated. In such a case, for each of the received 16-QAM symbols, only the multilayer demodulator 818 needs to determine in which quadrant the symbol has the least probability of error. Instead of choosing from the 16 possible 16-QAM symbols, only the multilayer demodulator 818 need only be determined based on 4 possible results (similar to QPSK demodulation). This is possible because the modulation symbol for each quadrant is not changed with respect to the base component bits. As described above, in some cases other modulation order combinations may be used.
Optionally, the receiver (in both the relay and base station) may monitor the signal strength and attempt to recover the signal without comparing the thresholds. In this case, the receiver always demodulates both the base and extension components. The base and extension components may indicate successful recovery of overhead messages according to error checks, such as a cyclic redundancy check (CRC) or a corresponding check result for each component.
In the embodiment shown in FIG. 1B, the UE device 102 may use multiple QoS communications in a single transmission, resulting in the use of efficient resources such as battery power and control-signaling overhead. Multiple services are provided in a single session. In addition, the use of WWAN uplink traffic resources is minimized for transmission, requiring only control signaling to facilitate multiple service transmission.
Those skilled in the art will appreciate that other embodiments and modifications of the specification and the invention are possible. The above description is provided for illustrative purposes. The present invention is therefore limited in scope only by the claims.
