WO2021035651A1

WO2021035651A1 - Unequal protection (uep) scheme using reed-solomon code

Info

Publication number: WO2021035651A1
Application number: PCT/CN2019/103458
Authority: WO
Inventors: Jian Li; Changlong Xu; Liangming WU; Hao Xu
Original assignee: Qualcomm Incorporated
Priority date: 2019-08-29
Filing date: 2019-08-29
Publication date: 2021-03-04

Abstract

Certain aspects of the present disclosure provide techniques for modulating data on a constellation. One example method generally includes encoding different portions of the data using different encoders.

Description

UNEQUAL PROTECTION (UEP) SCHEME USING REED-SOLOMON CODE

BACKGROUND

Field of the Disclosure

Aspects of the present disclosure relate to wireless communications, and more particularly, to techniques for modulation of data.

Description of Related Art

Wireless communication systems are widely deployed to provide various telecommunication services such as telephony, video, data, messaging, broadcasts, etc. These wireless communication systems may employ multiple-access technologies capable of supporting communication with multiple users by sharing available system resources (e.g., bandwidth, transmit power, etc. ) . Examples of such multiple-access systems include 3rd Generation Partnership Project (3GPP) Long Term Evolution (LTE) systems, LTE Advanced (LTE-A) systems, code division multiple access (CDMA) systems, time division multiple access (TDMA) systems, frequency division multiple access (FDMA) systems, orthogonal frequency division multiple access (OFDMA) systems, single-carrier frequency division multiple access (SC-FDMA) systems, and time division synchronous code division multiple access (TD-SCDMA) systems, to name a few.

In some examples, a wireless multiple-access communication system may include a number of base stations (BSs) , which are each capable of simultaneously supporting communication for multiple communication devices, otherwise known as user equipments (UEs) . In an LTE or LTE-A network, a set of one or more base stations may define an eNodeB (eNB) . In other examples (e.g., in a next generation, a new radio (NR) , or 5G network) , a wireless multiple access communication system may include a number of distributed units (DUs) (e.g., edge units (EUs) , edge nodes (ENs) , radio heads (RHs) , smart radio heads (SRHs) , transmission reception points (TRPs) , etc. ) in communication with a number of central units (CUs) (e.g., central nodes (CNs) , access node controllers (ANCs) , etc. ) , where a set of one or more DUs, in communication with a CU, may define an access node (e.g., which may be referred to as a BS, next generation NodeB (gNB or gNodeB) , TRP, etc. ) . A BS or DU may communicate with a set of UEs on downlink channels (e.g., for transmissions from a BS or DU to a UE) and uplink channels (e.g., for transmissions from a UE to a BS or DU) .

These multiple access technologies have been adopted in various telecommunication standards to provide a common protocol that enables different wireless devices to communicate on a municipal, national, regional, and even global level. New radio (e.g., 5G NR) is an example of an emerging telecommunication standard. NR is a set of enhancements to the LTE mobile standard promulgated by 3GPP. NR is designed to better support mobile broadband Internet access by improving spectral efficiency, lowering costs, improving services, making use of new spectrum, and better integrating with other open standards using OFDMA with a cyclic prefix (CP) on the downlink (DL) and on the uplink (UL) . To these ends, NR supports beamforming, multiple-input multiple-output (MIMO) antenna technology, and carrier aggregation.

However, as the demand for mobile broadband access continues to increase, there exists a need for further improvements in NR and LTE technology. Preferably, these improvements should be applicable to other multi-access technologies and the telecommunication standards that employ these technologies.

SUMMARY

The systems, methods, and devices of the disclosure each have several aspects, no single one of which is solely responsible for its desirable attributes. Without limiting the scope of this disclosure as expressed by the claims which follow, some features will now be discussed briefly. After considering this discussion, and particularly after reading the section entitled “Detailed Description” one will understand how the features of this disclosure provide advantages that include improved communications between access points and stations in a wireless network.

Certain aspects of the present disclosure provide techniques for modulating data on a constellation.

Certain aspects provide a method for wireless communication. The method generally includes partitioning information bits into first and second pluralities of information bits; encoding the first plurality of information bits information bits to obtain a first set of coded bits; encoding the second plurality of the information bits with a Reed-Solomon encoder to obtain a second set of bits; combining the first set of coded bits and the second set of coded bits into a symbol; and transmitting the symbol to a receiving device.

Certain aspects provide a method for wireless communication. The method generally includes receiving a modulated symbol from a transmitting device; demodulating a first portion of the modulated symbol to obtain a first set of coded bits; decoding the first set of coded bits to obtain a first set of information bits based at least in part on an encoder used at the transmitting device; demodulating a second portion of the modulated symbol to obtain a second set of coded bits; decoding the second set of coded bits to obtain a second set of information bits based at least in part on a Reed-Solomon encoder used at the transmitting device; and combining the first set of information bits and the second set of information bits.

Certain aspects provide an apparatus for wireless communication. The apparatus generally includes means for partitioning information bits into first and second pluralities of information bits; means for encoding the first plurality of information bits information bits to obtain a first set of coded bits; means for encoding the second plurality of the information bits with a Reed-Solomon encoder to obtain a second set of bits; means for combining the first set of coded bits and the second set of coded bits into a symbol; and means for transmitting the symbol to a receiving device.

Certain aspects provide an apparatus for wireless communication. The apparatus generally includes means for receiving a modulated symbol from a transmitting device; means for demodulating a first portion of the modulated symbol to obtain a first set of coded bits; means for decoding the first set of coded bits to obtain a first set of information bits based at least in part on an encoder used at the transmitting device; means for demodulating a second portion of the modulated symbol to obtain a second set of coded bits; means for decoding the second set of coded bits to obtain a second set of information bits based at least in part on a Reed-Solomon encoder used at the transmitting device; and means for combining the first set of information bits and the second set of information bits.

Certain aspects provide a method for wireless communication. The method generally includes receiving data modulated using a modulation scheme corresponding to a first constellation, wherein each symbol of the first constellation comprises a first bit sequence corresponding to a concatenation of a second bit sequence and a third bit sequence, and wherein the second bit sequence corresponds to a symbol of a second constellation and the third bit sequence corresponds a symbol of a third constellation, and demodulating the data based on the modulation scheme.

Certain aspects provide an apparatus for wireless communication. The apparatus generally includes a processing system configured to modulate data based on a modulation scheme corresponding to a first constellation, wherein each symbol of the first constellation comprises a first bit sequence corresponding to a concatenation of a second bit sequence and a third bit sequence, and wherein the second bit sequence corresponds to a symbol of a second constellation and the third bit sequence corresponds a symbol of a third constellation and a transmitter configured to transmit the data modulated using the first constellation.

Certain aspects provide an apparatus for wireless communication. The apparatus generally includes a receiver configured to receive data modulated using a modulation scheme corresponding to a first constellation, wherein each symbol of the first constellation comprises a first bit sequence corresponding to a concatenation of a second bit sequence and a third bit sequence, and wherein the second bit sequence corresponds to a symbol of a second constellation and the third bit sequence corresponds a symbol of a third constellation, and a processing system configured to demodulate the data based on the modulation scheme.

Certain aspects provide an apparatus for wireless communication. The apparatus generally includes means for modulating data based on a modulation scheme corresponding to a first constellation, wherein each symbol of the first constellation comprises a first bit sequence corresponding to a concatenation of a second bit sequence and a third bit sequence, and wherein the second bit sequence corresponds to a symbol of a second constellation and the third bit sequence corresponds a symbol of a third constellation, and means for transmitting the data modulated using the first constellation.

Certain aspects provide an apparatus for wireless communication. The apparatus generally includes means for receiving data modulated using a modulation scheme corresponding to a first constellation, wherein each symbol of the first constellation comprises a first bit sequence corresponding to a concatenation of a second bit sequence and a third bit sequence, and wherein the second bit sequence corresponds to a symbol of a second constellation and the third bit sequence corresponds a symbol of a third constellation, and means for demodulating the data based on the modulation scheme.

Certain aspects provide a computer-readable medium having instructions stored thereon to cause an apparatus to modulate data based on a modulation scheme corresponding to a first constellation, wherein each symbol of the first constellation comprises a first bit sequence corresponding to a concatenation of a second bit sequence and a third bit sequence, and wherein the second bit sequence corresponds to a symbol of a second constellation and the third bit sequence corresponds a symbol of a third constellation, and transmit the data modulated using the first constellation.

Certain aspects provide a computer-readable medium having instructions stored thereon to cause an apparatus to receive data modulated using a modulation scheme corresponding to a first constellation, wherein each symbol of the first constellation comprises a first bit sequence corresponding to a concatenation of a second bit sequence and a third bit sequence, and wherein the second bit sequence corresponds to a symbol of a second constellation and the third bit sequence corresponds a symbol of a third constellation, and demodulate the data based on the modulation scheme.

To the accomplishment of the foregoing and related ends, the one or more aspects comprise the features hereinafter fully described and particularly pointed out in the claims. The following description and the appended drawings set forth in detail certain illustrative features of the one or more aspects. These features are indicative, however, of but a few of the various ways in which the principles of various aspects may be employed.

BRIEF DESCRIPTION OF THE DRAWINGS

So that the manner in which the above-recited features of the present disclosure can be understood in detail, a more particular description, briefly summarized above, may be had by reference to aspects, some of which are illustrated in the drawings. It is to be noted, however, that the appended drawings illustrate only certain typical aspects of this disclosure and are therefore not to be considered limiting of its scope, for the description may admit to other equally effective aspects.

FIG. 1 is a block diagram conceptually illustrating an example telecommunications system, in accordance with certain aspects of the present disclosure.

FIG. 2 is a block diagram illustrating an example architecture of a distributed radio access network (RAN) , in accordance with certain aspects of the present disclosure.

FIG. 3 illustrates modulation mapping for various quadrature amplitude modulation (QAM) schemes, in accordance with certain aspects of the present disclosure.

FIG. 4 is a flow-diagram illustrating example operations for wireless communication, in accordance with certain aspects of the present disclosure.

FIG. 5 is a flow-diagram illustrating example operations for wireless communication, in accordance with certain aspects of the present disclosure.

FIGs. 6A and 6B illustrate the constellation, in accordance with certain aspects of the present disclosure.

FIG. 7 illustrates an example wireless communication system, in accordance with certain aspects of the present disclosure.

FIG. 8 illustrates a communications device that may include various components configured to perform operations for the techniques disclosed herein in accordance with aspects of the present disclosure.

FIG. 9 illustrates a communications device that may include various components configured to perform operations for the techniques disclosed herein in accordance with aspects of the present disclosure.

FIG. 10 illustrates mapping symbols to OFDM resources in accordance with aspects of the present disclosure.

To facilitate understanding, identical reference numerals have been used, where possible, to designate identical elements that are common to the figures. It is contemplated that elements disclosed in one aspect may be beneficially utilized on other aspects without specific recitation.

DETAILED DESCRIPTION

Aspects of the present disclosure provide apparatus, methods, processing systems, and computer readable mediums for modulating data in a constellation having relatively low reliability and relatively high reliability bits. For example, certain aspects are directed to techniques for designing a constellation that provide a consistent reliability gain difference between the low and high reliability bits of the constellation.

The following description provides examples, and is not limiting of the scope, applicability, or examples set forth in the claims. Changes may be made in the function and arrangement of elements discussed without departing from the scope of the disclosure. Various examples may omit, substitute, or add various procedures or components as appropriate. For instance, the methods described may be performed in an order different from that described, and various steps may be added, omitted, or combined. Also, features described with respect to some examples may be combined in some other examples. For example, an apparatus may be implemented or a method may be practiced using any number of the aspects set forth herein. In addition, the scope of the disclosure is intended to cover such an apparatus or method which is practiced using other structure, functionality, or structure and functionality in addition to, or other than, the various aspects of the disclosure set forth herein. It should be understood that any aspect of the disclosure disclosed herein may be embodied by one or more elements of a claim. The word “exemplary” is used herein to mean “serving as an example, instance, or illustration. ” Any aspect described herein as “exemplary” is not necessarily to be construed as preferred or advantageous over other aspects.

The techniques described herein may be used for various wireless communication technologies, such as 3GPP Long Term Evolution (LTE) , LTE-Advanced (LTE-A) , code division multiple access (CDMA) , time division multiple access (TDMA) , frequency division multiple access (FDMA) , orthogonal frequency division multiple access (OFDMA) , single-carrier frequency division multiple access (SC-FDMA) , time division synchronous code division multiple access (TD-SCDMA) , and other networks. The terms “network” and “system” are often used interchangeably.

A CDMA network may implement a radio technology such as Universal Terrestrial Radio Access (UTRA) , cdma2000, etc. UTRA includes Wideband CDMA (WCDMA) and other variants of CDMA. cdma2000 covers IS-2000, IS-95 and IS-856 standards. A TDMA network may implement a radio technology such as Global System for Mobile Communications (GSM) . An OFDMA network may implement a radio technology such as NR (e.g. 5G RA) , Evolved UTRA (E-UTRA) , Ultra Mobile Broadband (UMB) , IEEE 802.11 (Wi-Fi) , IEEE 802.16 (WiMAX) , IEEE 802.20, Flash- OFDMA, etc. UTRA and E-UTRA are part of Universal Mobile Telecommunication System (UMTS) . LTE and LTE-A are releases of UMTS that use E-UTRA. UTRA, E-UTRA, UMTS, LTE, LTE-A and GSM are described in documents from an organization named “3rd Generation Partnership Project” (3GPP) . cdma2000 and UMB are described in documents from an organization named “3rd Generation Partnership Project 2” (3GPP2) .

New Radio (NR) is an emerging wireless communications technology under development in conjunction with the 5G Technology Forum (5GTF) . NR access (e.g., 5G NR) may support various wireless communication services, such as enhanced mobile broadband (eMBB) targeting wide bandwidth (e.g., 80 MHz or beyond) , millimeter wave (mmW) targeting high carrier frequency (e.g., 25 GHz or beyond) , massive machine type communications MTC (mMTC) targeting non-backward compatible MTC techniques, and/or mission critical targeting ultra-reliable low-latency communications (URLLC) . These services may include latency and reliability requirements. These services may also have different transmission time intervals (TTI) to meet respective quality of service (QoS) requirements. In addition, these services may co-exist in the same subframe.

The techniques described herein may be used for the wireless networks and radio technologies mentioned above as well as other wireless networks and radio technologies. For clarity, while aspects may be described herein using terminology commonly associated with 3G and/or 4G wireless technologies, aspects of the present disclosure can be applied in other generation-based communication systems, such as 5G and later, including NR technologies.

FIG. 1 illustrates an example wireless communication network 100 in which aspects of the present disclosure may be performed. For example, the wireless communication network 100 may be an NR system (e.g., a 5G NR network) . For example, as shown in FIG. 1, the UE 120a may have a modulation module that may be configured for modulating data in a constellation, according to aspects described herein. For example, as shown in FIG. 1, the BS 110a may have demodulation module that may be configured for demodulate the data modulating in the constellation, according to aspects described herein.

As illustrated in FIG. 1, the wireless communication network 100 may include a number of base stations (BSs) 110 and other network entities. A BS may be a station that communicates with user equipments (UEs) . Each BS 110 may provide communication coverage for a particular geographic area. In 3GPP, the term “cell” can refer to a coverage area of a Node B (NB) and/or a NB subsystem serving this coverage area, depending on the context in which the term is used. In NR systems, the term “cell” and BS, next generation NodeB (gNB or gNodeB) , access point (AP) , distributed unit (DU) , carrier, or transmission reception point (TRP) may be used interchangeably. In some examples, a cell may not necessarily be stationary, and the geographic area of the cell may move according to the location of a mobile BS. In some examples, the BSs may be interconnected to one another and/or to one or more other BSs or network nodes (not shown) in wireless communication network 100 through various types of backhaul interfaces, such as a direct physical connection, a wireless connection, a virtual network, or the like using any suitable transport network.

In general, any number of wireless networks may be deployed in a given geographic area. Each wireless network may support a particular radio access technology (RAT) and may operate on one or more frequencies. A RAT may also be referred to as a radio technology, an air interface, etc. A frequency may also be referred to as a carrier, a subcarrier, a frequency channel, a tone, a subband, etc. Each frequency may support a single RAT in a given geographic area in order to avoid interference between wireless networks of different RATs. In some cases, NR or 5G RAT networks may be deployed.

A BS may provide communication coverage for a macro cell, a pico cell, a femto cell, and/or other types of cells. A macro cell may cover a relatively large geographic area (e.g., several kilometers in radius) and may allow unrestricted access by UEs with service subscription. A pico cell may cover a relatively small geographic area and may allow unrestricted access by UEs with service subscription. A femto cell may cover a relatively small geographic area (e.g., a home) and may allow restricted access by UEs having an association with the femto cell (e.g., UEs in a Closed Subscriber Group (CSG) , UEs for users in the home, etc. ) . A BS for a macro cell may be referred to as a macro BS. A BS for a pico cell may be referred to as a pico BS. A BS for a femto cell may be referred to as a femto BS or a home BS. In the example shown in FIG. 1, the

BSs

110a, 110b and 110c may be macro BSs for the

macro cells

102a, 102b and 102c, respectively. The BS 110x may be a pico BS for a pico cell 102x. The BSs 110y and 110z may be femto BSs for the

femto cells

102y and 102z, respectively. A BS may support one or multiple (e.g., three) cells.

Wireless communication network 100 may also include relay stations. A relay station is a station that receives a transmission of data and/or other information from an upstream station (e.g., a BS or a UE) and sends a transmission of the data and/or other information to a downstream station (e.g., a UE or a BS) . A relay station may also be a UE that relays transmissions for other UEs. In the example shown in FIG. 1, a relay station 110r may communicate with the BS 110a and a UE 120r in order to facilitate communication between the BS 110a and the UE 120r. A relay station may also be referred to as a relay BS, a relay, etc.

Wireless communication network 100 may be a heterogeneous network that includes BSs of different types, e.g., macro BS, pico BS, femto BS, relays, etc. These different types of BSs may have different transmit power levels, different coverage areas, and different impact on interference in the wireless communication network 100. For example, macro BS may have a high transmit power level (e.g., 20 Watts) whereas pico BS, femto BS, and relays may have a lower transmit power level (e.g., 1 Watt) .

Wireless communication network 100 may support synchronous or asynchronous operation. For synchronous operation, the BSs may have similar frame timing, and transmissions from different BSs may be approximately aligned in time. For asynchronous operation, the BSs may have different frame timing, and transmissions from different BSs may not be aligned in time. The techniques described herein may be used for both synchronous and asynchronous operation.

A network controller 130 may couple to a set of BSs and provide coordination and control for these BSs. The network controller 130 may communicate with the BSs 110 via a backhaul. The BSs 110 may also communicate with one another (e.g., directly or indirectly) via wireless or wireline backhaul.

The UEs 120 (e.g., 120x, 120y, etc. ) may be dispersed throughout the wireless communication network 100, and each UE may be stationary or mobile. A UE may also be referred to as a mobile station, a terminal, an access terminal, a subscriber unit, a station, a Customer Premises Equipment (CPE) , a cellular phone, a smart phone, a personal digital assistant (PDA) , a wireless modem, a wireless communication device, a handheld device, a laptop computer, a cordless phone, a wireless local loop (WLL) station, a tablet computer, a camera, a gaming device, a netbook, a smartbook, an ultrabook, an appliance, a medical device or medical equipment, a biometric sensor/device, a wearable device such as a smart watch, smart clothing, smart glasses, a smart wrist band, smart jewelry (e.g., a smart ring, a smart bracelet, etc. ) , an entertainment device (e.g., a music device, a video device, a satellite radio, etc. ) , a vehicular component or sensor, a smart meter/sensor, industrial manufacturing equipment, a global positioning system device, or any other suitable device that is configured to communicate via a wireless or wired medium. Some UEs may be considered machine-type communication (MTC) devices or evolved MTC (eMTC) devices. MTC and eMTC UEs include, for example, robots, drones, remote devices, sensors, meters, monitors, location tags, etc., that may communicate with a BS, another device (e.g., remote device) , or some other entity. A wireless node may provide, for example, connectivity for or to a network (e.g., a wide area network such as Internet or a cellular network) via a wired or wireless communication link. Some UEs may be considered Internet-of-Things (IoT) devices, which may be narrowband Iot (NB-IoT) devices.

Certain wireless networks (e.g., LTE) utilize orthogonal frequency division multiplexing (OFDM) on the downlink and single-carrier frequency division multiplexing (SC-FDM) on the uplink. OFDM and SC-FDM partition the system bandwidth into multiple (K) orthogonal subcarriers, which are also commonly referred to as tones, bins, etc. Each subcarrier may be modulated with data. In general, modulation symbols are sent in the frequency domain with OFDM and in the time domain with SC-FDM. The spacing between adjacent subcarriers may be fixed, and the total number of subcarriers (K) may be dependent on the system bandwidth. For example, the spacing of the subcarriers may be 15 kHz and the minimum resource allocation (called a “resource block” (RB) ) may be 12 subcarriers (or 180 kHz) . Consequently, the nominal Fast Fourier Transfer (FFT) size may be equal to 128, 256, 512, 1024 or 2048 for system bandwidth of 1.25, 2.5, 5, 10, or 20 megahertz (MHz) , respectively. The system bandwidth may also be partitioned into subbands. For example, a subband may cover 1.8 MHz (e.g., 6 RBs) , and there may be 1, 2, 4, 8, or 16 subbands for system bandwidth of 1.25, 2.5, 5, 10 or 20 MHz, respectively. In LTE, the basic transmission time interval (TTI) or packet duration is the 1 ms subframe. In NR, a subframe is still 1 ms, but the basic TTI is referred to as a slot. A subframe contains a variable number of slots (e.g., 1, 2, 4, 8, 16, ... slots) depending on the subcarrier spacing. The NR RB is 12 consecutive frequency subcarriers. NR may support a base subcarrier spacing of 15 KHz and other subcarrier spacing may be defined with respect to the base subcarrier spacing, for example, 30 kHz, 60 kHz, 120 kHz, 240 kHz, etc. The symbol and slot lengths scale with the subcarrier spacing. The CP length also depends on the subcarrier spacing.

NR may utilize OFDM with a CP on the uplink and downlink and include support for half-duplex operation using TDD. Beamforming may be supported and beam direction may be dynamically configured. MIMO transmissions with precoding may also be supported. In some examples, MIMO configurations in the DL may support up to 8 transmit antennas with multi-layer DL transmissions up to 8 streams and up to 2 streams per UE. In some examples, multi-layer transmissions with up to 2 streams per UE may be supported. Aggregation of multiple cells may be supported with up to 8 serving cells.

In some examples, access to the air interface may be scheduled. A scheduling entity (e.g., a BS) allocates resources for communication among some or all devices and equipment within its service area or cell. The scheduling entity may be responsible for scheduling, assigning, reconfiguring, and releasing resources for one or more subordinate entities. That is, for scheduled communication, subordinate entities utilize resources allocated by the scheduling entity. Base stations are not the only entities that may function as a scheduling entity. In some examples, a UE may function as a scheduling entity and may schedule resources for one or more subordinate entities (e.g., one or more other UEs) , and the other UEs may utilize the resources scheduled by the UE for wireless communication. In some examples, a UE may function as a scheduling entity in a peer-to-peer (P2P) network, and/or in a mesh network. In a mesh network example, UEs may communicate directly with one another in addition to communicating with a scheduling entity.

In some examples, two or more subordinate entities (e.g., UEs) may communicate with each other using sidelink signals. Real-world applications of such sidelink communications may include public safety, proximity services, UE-to-network relaying, vehicle-to-vehicle (V2V) communications, Intemet of Everything (IoE) communications, Iot communications, mission-critical mesh, and/or various other suitable applications. Generally, a sidelink signal may refer to a signal communicated from one subordinate entity (e.g., UE1) to another subordinate entity (e.g., UE2) without relaying that communication through the scheduling entity (e.g., UE or BS) , even though the scheduling entity may be utilized for scheduling and/or control purposes. In some examples, the sidelink signals may be communicated using a licensed spectrum (unlike wireless local area networks, which typically use an unlicensed spectrum) .

In FIG. 1, a solid line with double arrows indicates desired transmissions between a UE and a serving BS, which is a BS designated to serve the UE on the downlink and/or uplink. A finely dashed line with double arrows indicates potentially interfering transmissions between a UE and a BS.

FIG. 2 illustrates example components of BS 110 and UE 120 (e.g., in the wireless communication network 100 of FIG. 1) , which may be used to implement aspects of the present disclosure. For example, antennas 252,

processors

266, 258, 264, and/or controller/processor 280 of the UE 120 and/or antennas 234,

processors

220, 230, 238, and/or controller/processor 240 of the BS 110 may be used to perform the various techniques and methods described herein.

At the BS 110, a transmit processor 220 may receive data from a data source 212 and control information from a controller/processor 240. The control information may be for the physical broadcast channel (PBCH) , physical control format indicator channel (PCFICH) , physical hybrid ARQ indicator channel (PHICH) , physical downlink control channel (PDCCH) , group common PDCCH (GC PDCCH) , etc. The data may be for the physical downlink shared channel (PDSCH) , etc. The processor 220 may process (e.g., encode and symbol map) the data and control information to obtain data symbols and control symbols, respectively. The transmit processor 220 may also generate reference symbols, such as for the primary synchronization signal (PSS) , secondary synchronization signal (SSS) , and cell-specific reference signal (CRS) . A transmit (TX) multiple-input multiple-output (MIMO) processor 230 may perform spatial processing (e.g., precoding) on the data symbols, the control symbols, and/or the reference symbols, if applicable, and may provide output symbol streams to the modulators (MODs) 232a-232t. Each modulator 232 may process a respective output symbol stream (e.g., for OFDM, etc. ) to obtain an output sample stream. Each modulator may further process (e.g., convert to analog, amplify, filter, and upconvert) the output sample stream to obtain a downlink signal. Downlink signals from modulators 232a-232t may be transmitted via the antennas 234a-234t, respectively. In certain aspects, the modulator 232 may be configured to modulate data via a constellation having unequal protection, as described in more detail herein.

At the UE 120, the antennas 252a-252r may receive the downlink signals from the BS 110 and may provide received signals to the demodulators (DEMODs) in transceivers 254a-254r, respectively. Each demodulator 254 may condition (e.g., filter, amplify, downconvert, and digitize) a respective received signal to obtain input samples. Each demodulator may further process the input samples (e.g., for OFDM, etc. ) to obtain received symbols. In certain aspects, the demodulator 254 may be configured to demodulate data modulated in a constellation having unequal protection, as described in more detail herein. A MIMO detector 256 may obtain received symbols from all the demodulators 254a-254r, perform MIMO detection on the received symbols if applicable, and provide detected symbols. A receive processor 258 may process (e.g., demodulate, deinterleave, and decode) the detected symbols, provide decoded data for the UE 120 to a data sink 260, and provide decoded control information to a controller/processor 280.

On the uplink, at UE 120, a transmit processor 264 may receive and process data (e.g., for the physical uplink shared channel (PUSCH) ) from a data source 262 and control information (e.g., for the physical uplink control channel (PUCCH) from the controller/processor 280. The transmit processor 264 may also generate reference symbols for a reference signal (e.g., for the sounding reference signal (SRS)) . The symbols from the transmit processor 264 may be precoded by a TX MIMO processor 266 if applicable, further processed by the demodulators in transceivers 254a-254r (e.g., for SC-FDM, etc. ) , and transmitted to the base station 110. At the BS 110, the uplink signals from the UE 120 may be received by the antennas 234, processed by the modulators 232, detected by a MIMO detector 236 if applicable, and further processed by a receive processor 238 to obtain decoded data and control information sent by the UE 120. The receive processor 238 may provide the decoded data to a data sink 239 and the decoded control information to the controller/processor 240.

The controllers/

processors

240 and 280 may direct the operation at the BS 110 and the UE 120, respectively. The controller/processor 240 and/or other processors and modules at the BS 110 may perform or direct the execution of processes for the techniques described herein. The

memories

242 and 282 may store data and program codes for BS 110 and UE 120, respectively. A scheduler 244 may schedule UEs for data transmission on the downlink and/or uplink.

EXAMPLE UNEQUAL PROTECTION (UEP) DESIGN FOR HIGH-ORDER MODULATION

Aspects of the present disclosure provide apparatus, methods, processing systems, and computer readable mediums for modulating data in a constellation having relatively low reliability and relatively high reliability bits. For example, certain aspects are directed to techniques for designing a constellation that provide a consistent (e.g., fixed) reliability gain difference between the low and high reliability bits of the constellation. Certain aspects enable an increase in data throughput by modulating uncoded bits onto the high reliability bits of the constellation.

FIG. 3 illustrates modulation mapping for various quadrature amplitude modulation (QAM) schemes, in accordance with certain aspects of the present disclosure. As illustrated, the constellation 302 represents a 4-QAM constellation. The constellation 302 is represented in FIG. 3 in a two-dimensional plane divided into four

quadrants

304, 306, 308, and 310. The four points (e.g., also referred to herein as symbols, or modulation-symbols) , one point in each

quadrant

304, 306, 308, 310, represent four different signaling alternatives associated with 4-QAM. 4-QAM allows for modulation of up to 2-bits (referred to as bits b0, b1, where b0 is the least significant bit and b1 is the most significant bit) of information during each modulation-symbol interval. For example, the bottom left symbol may represent the binary value “01” , the bottom right symbol may represent the binary value “00” , the top left symbol may represent the binary value “11” , and the top right symbol may represent the binary value “10. ”

The constellation 312 represents a 16-QAM constellation. Extending to 16-QAM modulation allows for the availability of sixteen different signaling alternatives. With 16QAM, up to 4-bits (referred to as bits b0, b1, b2, b3, where b0 is the least significant bit and b3 is the most significant bit) of information can be modulated in each modulation-symbol interval as illustrated by the points (e.g., symbols) in each of the

quadrants

314, 316, 318, 320. For example, the bottom left symbol in quadrant 318 may represent the binary value “0000” , the bottom right symbol in quadrant 320 may represent the binary value “1000” , the top left symbol in quadrant 316 may represent the binary value “0010” , and the top right symbol in quadrant 314 may represent the binary value “1010. ”

The constellation 322 represents a 64-QAM constellation. The modulation schemes may be further extended to a 64QAM, which provides sixty-four different signaling alternatives. In this case, up to 6-bits (referred to as bits b0, b1, b2, b3, b4, b5, where b0 is the least significant bit and b5 is the most significant bit) of information may be modulated in each modulation-symbol interval. The constellation 322 is broken up into four

quadrants

324, 326, 328, 330, as illustrated.

Different bits of constellations, such as

constellations

302, 312, 322, may have different reliabilities (e.g., bit error rates) . For example, for a 64-QAM constellation, the reliability of bits b2 and b5 may be the same and greater than the reliability of bits b1 and b4. Moreover, the reliability of bits b1 and b4 may be the same and greater than the reliability of bits b0 and b3. The reliability of bits b0 and b3 may be the same. The gap in the reliability of the bits (e.g., between bits b2 and b1) may be around 1.2 dB.

Moreover, up to 8 bits (e.g., referred to as bits b0, b1, b2, b3, b4, b5, b6, b7, where b0 is the least significant bit and b7 is the most significant bit) of information may be modulated in each modulation-symbol interval of a 256-QAM constellation. The reliability of bits b3 and b7 may be the same and greater than bits b2 and b6. The reliability of bits b2 and b6 may be the same and greater than the reliability of bits b1 and b5. The reliability of bits b1 and b5 may be the same and greater than the reliability of bits b0 and b4. The reliability of bits b0 and b4 may be the same. The gap in the reliability of the bits (e.g., between bit b2 and b1) may be around 1.4 dB.

In some cases, multiple redundancy versions (RVs) of information may be modulated and transmitted. For example, if a negative acknowledgement (NACK) is received after the transmission of a data channel, one or more RVs of the data channel may be transmitted. The first RV may be referred to as RV0, the second RV may be referred to as RV1, and so on. For RV0, systematic bits of the data may be modulated in high reliability bits of the QAM symbols since systematic bits are more important than parity check bits that are used for error correction. However, the drawback to this approach is that the number of steps in the reliability of bits associated with different QAM modulation schemes is variable, as described with respect to FIG. 3. For example, there are two steps of reliability associated with 16-QAM, three steps of reliability associated with 64-QAM, and four steps of reliability associated with 256-QAM. Moreover, the step size in the reliability of the bits is not consistent for different QAM modulation schemes. For example, a reliability gap of 1.2 dB is present for 64-QAM, whereas a reliability gap of 1.4 dB is present for 256-QAM.

Certain aspect of the present disclosure are directed to a design approach of a constellation that enables setting a specific reliability gap and a specific number (e.g., single) of reliability steps. For example, certain aspects described herein provide a constellation having a single reliability step with a reliability gap of around 6 dB. For instance, a constellation (e.g., constellation 322) may be implemented based on a concatenation of two other constellations (e.g., constellations 302, 312) . The 6 bits of information in each symbol of the constellation 322 may have a bit sequence that is implemented by concatenating the bit sequence of respective symbols from the

constellations

302, 312, as described in more detail herein.

FIG. 4 is a flow-diagram illustrating example operations 400 for wireless communication, in accordance with certain aspects of the present disclosure. The operations 400 may be performed by a transmitter device, such as the base station 110 or the UE 120.

Operations 400 may be implemented as software components that are executed and run on one or more processors (e.g., controller/processor 240 of FIG. 2) . Further, the transmission and reception of signals by the BS in operations 400 may be enabled, for example, by one or more antennas (e.g., antennas 234 of FIG. 2) . In certain aspects, the transmission and/or reception of signals by the BS may be implemented via a bus interface of one or more processors (e.g., controller/processor 240) obtaining and/or outputting signals.

The operations 400 begin, at block 402, by the transmitter device modulating data based on a modulation scheme corresponding to a first constellation (e.g., constellation 322) . Each symbol of the first constellation may include a first bit sequence corresponding to a concatenation of a second bit sequence and a third bit sequence. For example, the second bit sequence may correspond to a symbol of a second constellation (e.g., constellation 302) , and the third bit sequence may correspond to a symbol of a third constellation (e.g., constellation 312) . in some cases, a subset (e.g., high reliability bits) of the first bit sequences of the symbols in each quadrant of the first constellation may correspond to the second bit sequence of the symbol in a respective quadrant of the second constellation, as described in more detail herein with respect to FIG. 6.

In certain aspects, the second constellation may be an M-QAM constellation, M being equal to 2 ^m, and m being an integer greater than or equal to 1. In other words, m may represent the number of bits of each symbol (e.g., m may be 6 for 64-QAM) . The second constellation may be an N-QAM constellation, N being equal to 2 ⁿ, and n being an integer greater than or equal to 1. The second bit sequence may be associated with a higher reliability than the third bit sequence, as described in more detail herein with respect to FIG. 6. At block 404, the transmitter device may transmit the data modulated using the first constellation.

FIG. 5 is a flow-diagram illustrating example operations 500 for wireless communication, in accordance with certain aspects of the present disclosure. The operations 500 may be performed by a receiver device, such as the base station 110 or the UE 120.

The operations 500 may be complimentary operations by the receiver device to the operations 400 performed by the transmitter device. Operations 500 may be implemented as software components that are executed and run on one or more processors (e.g., controller/processor 280 of FIG. 2) . Further, the transmission and reception of signals by the receiver device in operations 500 may be enabled, for example, by one or more antennas (e.g., antennas 252 of FIG. 2) . In certain aspects, the transmission and/or reception of signals by the receiver device may be implemented via a bus interface of one or more processors (e.g., controller/processor 280) obtaining and/or outputting signals.

The operations 500 begin, at block 502, by the receiver device receiving data modulated using a modulation scheme corresponding to a first constellation. Each symbol of the first constellation may include a first bit sequence corresponding to a concatenation of a second bit sequence and a third bit sequence. The second bit sequence may correspond to a symbol of a second constellation and the third bit sequence may correspond to a symbol of a third constellation. At block 504, the receiver device may demodulate the data based on the modulation scheme.

FIG. 6A illustrates the constellation 322, in accordance with certain aspects of the present disclosure. Designing the constellation 322 may include generating one Gray coded M-QAM (e.g., M being 4 for 4-QAM) constellation with M = 2 ^m, m being an integer equal to or greater than 1, and generating another Gray coded N-QAM (e.g., N being 16 for 16-QAM) constellation with N = 2 ⁿ, n being an integer equal to or greater than 1.

The bit sequences of the M-QAM constellation, as a set, may be concatenated with the bit sequences in each symbol of the second N-QAM constellation. For example, the sequence for each symbol of the constellation 322 may be implemented by concatenating the n bits and m bits. For instance, the bits (e.g., b0, b1, b2, b3) of the constellation 322 may be relatively low reliable bits (also referred to as bits I ₁, I ₂, I ₃, I ₄) and correspond to the constellation 312 in each of the four quadrants. Moreover, the bits b4, b5 of the constellation 322 may be relative high reliable bits (also referred to as bits h ₁, h ₂) and correspond to the constellation 302. For example, the bits h1, h2 of symbols in the top right quadrant of the constellation 322 may have a binary value of “10” (e.g., corresponding to the binary value “10” in the top right quadrant of constellation 302) , the bits h1, h2 of symbols in the top left quadrant of the constellation 322 may have a binary value of “11” (e.g., corresponding to the binary value “11” in the top left quadrant of constellation 302) , and so on.

In other words, the symbols in the top right quadrant 324 of the constellation 322 may be implemented by concatenating a bit sequence of respective symbols of the constellation 312 with a bit sequence of the top right symbol or quadrant (e.g., quadrant 304 as illustrated in FIG. 3) of the constellation 302. Similarly, the symbols in the top left quadrant 326 (e.g., as illustrated in FIG. 3) of the constellation 322 may be implemented by concatenating a bit sequence of respective symbols of the constellation 312 with a bit sequence of the top left symbol or quadrant (e.g., quadrant 306 as illustrated in FIG. 3) of the constellation 302, and so on.

In this manner, bits b0 and b1 of symbols in the top left quadrant of constellation 322 may be “11” corresponding to top left quadrant of constellation 302, bits b0 and b1 of symbols in the top right quadrant of constellation 322 may be “10” corresponding to top right quadrant of constellation 302, bits b0 and b1 of symbols in the bottom left quadrant of constellation 322 may be “01” corresponding to bottom left quadrant of constellation 302, and bits b0 and b1 of symbols in the bottom right quadrant of constellation 322 may be “00” corresponding to bottom right quadrant of constellation 302 As shown in FIG. 6B, the bit sequence of symbol 602 may be “110000” and implemented by concatenating the bit sequence “11” from the constellation 302 with the bit sequence “0000” from the constellation 312. The bit sequence of symbol 604 may be “010000” and implemented by concatenating the bit sequence “01” from the constellation 302 with the bit sequence “0000” from the constellation 312. The bit sequence of symbol 606 may be “000000” and implemented by concatenating the bit sequence “00” from the constellation 302 with the bit sequence “0000” from the constellation 312. The bit sequence of symbol 608 may be “100000” and implemented by concatenating the bit sequence “10” from the constellation 302 with the bit sequence “0000” from the constellation 312. In FIG. 6B, the bits shown in bold may be encoded using an RS encoder.

By implementing a constellation with relatively higher reliability bits and relative lower reliability bits, the more important bits (e.g., systematic bits) may be modulated on the higher reliability bits and less important bits (e.g., parity bits) may be modulated on the lower reliability bits. In certain aspects, uncoded bits may be modulated on the higher reliability bits, and coded bits may be implemented on the lower reliability bits, as described in more detail with respect to FIG. 7.

FIG. 7 illustrates an example wireless communication system 700, in accordance with certain aspects of the present disclosure. As illustrated, information bits may be received at an input of a demultiplexer 702, which may be a serial-to-parallel converter. The demultiplexer 702 generates a first subset (also referred to as a first portion) of the information bits which may be input to a channel coding module 704. The channel coding module 704 may use different channel coding combinations such that the reliability of each bit of the first subset of the information bits is balanced when modulated on low reliability bits of the constellation 322.

The demultiplexer 702 may also generate a second subset (also referred to as a second portion) of the information bits. The first and second subsets of bits need not have the same number of bits. In certain aspects, the second subset of bits may remain uncoded. The uncoded second subset of the information bits and the coded first subset of the information bits may be multiplexed via the multiplexer 708 to generate a multiplexed signal. The multiplexed signal having both the coded first subset of the information bits and the uncoded second subset of the information bits may be received by a UEP modulation module 710 (e.g., corresponding to the modulators 232 described with respect to FIG. 2) . The UEP modulation module 710 modulates the coded first subset of the information bits on the relatively low reliability bits, and modulates the uncoded second subset of the information bits on the relatively high reliability bits of the constellation 322, as described herein. The modulated symbols may then be mapped to OFDM resources by resource mapper 712. In an aspect, the symbols may be mapped first by time domain index and then by frequency domain index as shown in FIG. 10. The time domain and frequency domain indices may be in increasing order; alternatively, one may be increasing and the other decreasing. Mapping in the time domain first may concentrate bits likely to receive an error in channel fading conditions into those bits using the RS code.

In certain aspects, the second subset of the information bits may be optionally coded via a channel coding module 706. In some cases, the channel coding module 706 may code the second subset of the information bits with a lower coding gain as compared to coding of the first subset of the information bits since the second subset is modulated on the higher reliability bits of the constellation 322. In an aspect, channel coding module 706 may encode the second subset of the information bits using a forward error correcting code. The UEP modulation module 710 modulates the coded first subset of the information bits on the relatively low reliability bits and modulates the coded (e.g., with a lower coding gain) second subset of the information bits on the relatively high reliability bits of the constellation 322.

At the receiver, the low reliability bits may be demodulated (e.g., via the demodulators 254) . For example, the log-likelihood ratio associated with the low reliability bits may be determined. The low-reliability bits may then be decoded. The decoded low reliability bits may then be used to decode and determine the value of the high reliability bits.

While examples provided herein have described a design of a 64-QAM constellation using 4-QAM and 16-QAM constellations to facilitate understanding, any suitable constellation may be designed with this approach. For example, a 256-QAM constellation may be designed using 4-QAM and 64-QAM constellations in a similar manner.

FIG. 8 illustrates a communications device 800 that may include various components (e.g., corresponding to means-plus-function components) configured to perform operations for the techniques disclosed herein, such as the operations illustrated in FIG. 4. The communications device 800 includes a processing system 802 coupled to a transceiver 808. The transceiver 808 is configured to transmit and receive signals for the communications device 800 via an antenna 810, such as the various signals as described herein. The processing system 802 may be configured to perform processing functions for the communications device 800, including processing signals received and/or to be transmitted by the communications device 800.

The processing system 802 includes a processor 804 coupled to a computer-readable medium/memory 812 via a bus 806. In certain aspects, the computer-readable medium/memory 812 is configured to store instructions (e.g., computer-executable code) that when executed by the processor 804, cause the processor 804 to perform the operations illustrated in FIG. 4, or other operations for performing the various techniques discussed herein. In certain aspects, computer-readable medium/memory 812 stores code for modulation 814, code for transmission 816, and code for channel coding 818. In certain aspects, the processor 804 has circuitry configured to implement the code stored in the computer-readable medium/memory 812. The processor 804 includes circuitry for modulation 820, circuitry for transmission 824, and circuitry for channel coding 826.

FIG. 9 illustrates a communications device 900 that may include various components (e.g., corresponding to means-plus-function components) configured to perform operations for the techniques disclosed herein, such as the operations illustrated in FIG. 5. The communications device 900 includes a processing system 902 coupled to a transceiver 908. The transceiver 908 is configured to transmit and receive signals for the communications device 900 via an antenna 910, such as the various signals as described herein. The processing system 902 may be configured to perform processing functions for the communications device 900, including processing signals received and/or to be transmitted by the communications device 900.

The processing system 902 includes a processor 904 coupled to a computer-readable medium/memory 912 via a bus 906. In certain aspects, the computer-readable medium/memory 912 is configured to store instructions (e.g., computer-executable code) that when executed by the processor 904, cause the processor 904 to perform the operations illustrated in FIG. 5, or other operations for performing the various techniques discussed herein. In certain aspects, computer-readable medium/memory 912 stores code for demodulation 914, code for reception 916, and code for decoding 918. In certain aspects, the processor 904 has circuitry configured to implement the code stored in the computer-readable medium/memory 912. The processor 904 includes circuitry for demodulation 920, circuitry for reception 924, and circuitry for decoding 926.

The methods disclosed herein comprise one or more steps or actions for achieving the methods. The method steps and/or actions may be interchanged with one another without departing from the scope of the claims. In other words, unless a specific order of steps or actions is specified, the order and/or use of specific steps and/or actions may be modified without departing from the scope of the claims.

As used herein, a phrase referring to “at least one of” a list of items refers to any combination of those items, including single members. As an example, “at least one of: a, b, or c” is intended to cover a, b, c, a-b, a-c, b-c, and a-b-c, as well as any combination with multiples of the same element (e.g., a-a, a-a-a, a-a-b, a-a-c, a-b-b, a-c-c, b-b, b-b-b, b-b-c, c-c, and c-c-c or any other ordering of a, b, and c) .

As used herein, the term “determining” encompasses a wide variety of actions. For example, “determining” may include calculating, computing, processing, deriving, investigating, looking up (e.g., looking up in a table, a database or another data structure) , ascertaining and the like. Also, “determining” may include receiving (e.g., receiving information) , accessing (e.g., accessing data in a memory) and the like. Also, “determining” may include resolving, selecting, choosing, establishing and the like.

The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but is to be accorded the full scope consistent with the language of the claims, wherein reference to an element in the singular is not intended to mean “one and only one” unless specifically so stated, but rather “one or more. ” Unless specifically stated otherwise, the term “some” refers to one or more. All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. No claim element is to be construed under the provisions of 35 U.S.C. §112 (f) unless the element is expressly recited using the phrase “means for” or, in the case of a method claim, the element is recited using the phrase “step for. ”

The various operations of methods described above may be performed by any suitable means capable of performing the corresponding functions. The means may include various hardware and/or software component (s) and/or module (s) , including, but not limited to a circuit, an application specific integrated circuit (ASIC) , or processor. Generally, where there are operations illustrated in figures, those operations may have corresponding counterpart means-plus-function components with similar numbering.

The various illustrative logical blocks, modules and circuits described in connection with the present disclosure may be implemented or performed with a general purpose processor, a digital signal processor (DSP) , an application specific integrated circuit (ASIC) , a field programmable gate array (FPGA) or other programmable logic device (PLD) , discrete gate or transistor logic, discrete hardware components, or any combination thereof designed to perform the functions described herein. A general-purpose processor may be a microprocessor, but in the alternative, the processor may be any commercially available processor, controller, microcontroller, or state machine. A processor may also be implemented as a combination of computing devices, e.g., a combination of a DSP and a microprocessor, a plurality of microprocessors, one or more microprocessors in conjunction with a DSP core, or any other such configuration.

If implemented in hardware, an example hardware configuration may comprise a processing system in a wireless node. The processing system may be implemented with a bus architecture. The bus may include any number of interconnecting buses and bridges depending on the specific application of the processing system and the overall design constraints. The bus may link together various circuits including a processor, machine-readable media, and a bus interface. The bus interface may be used to connect a network adapter, among other things, to the processing system via the bus. The network adapter may be used to implement the signal processing functions of the PHY layer. In the case of a user terminal 120 (see FIG. 1) , a user interface (e.g., keypad, display, mouse, joystick, etc. ) may also be connected to the bus. The bus may also link various other circuits such as timing sources, peripherals, voltage regulators, power management circuits, and the like, which are well known in the art, and therefore, will not be described any further. The processor may be implemented with one or more general-purpose and/or special-purpose processors. Examples include microprocessors, microcontrollers, DSP processors, and other circuitry that can execute software. Those skilled in the art will recognize how best to implement the described functionality for the processing system depending on the particular application and the overall design constraints imposed on the overall system.

If implemented in software, the functions may be stored or transmitted over as one or more instructions or code on a computer readable medium. Software shall be construed broadly to mean instructions, data, or any combination thereof, whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise. Computer-readable media include both computer storage media and communication media including any medium that facilitates transfer of a computer program from one place to another. The processor may be responsible for managing the bus and general processing, including the execution of software modules stored on the machine-readable storage media. A computer-readable storage medium may be coupled to a processor such that the processor can read information from, and write information to, the storage medium. In the alternative, the storage medium may be integral to the processor. By way of example, the machine-readable media may include a transmission line, a carrier wave modulated by data, and/or a computer readable storage medium with instructions stored thereon separate from the wireless node, all of which may be accessed by the processor through the bus interface. Alternatively, or in addition, the machine-readable media, or any portion thereof, may be integrated into the processor, such as the case may be with cache and/or general register files. Examples of machine-readable storage media may include, by way of example, RAM (Random Access Memory) , flash memory, ROM (Read Only Memory) , PROM (Programmable Read-Only Memory) , EPROM (Erasable Programmable Read-Only Memory) , EEPROM (Electrically Erasable Programmable Read-Only Memory) , registers, magnetic disks, optical disks, hard drives, or any other suitable storage medium, or any combination thereof. The machine-readable media may be embodied in a computer-program product.

A software module may comprise a single instruction, or many instructions, and may be distributed over several different code segments, among different programs, and across multiple storage media. The computer-readable media may comprise a number of software modules. The software modules include instructions that, when executed by an apparatus such as a processor, cause the processing system to perform various functions. The software modules may include a transmission module and a receiving module. Each software module may reside in a single storage device or be distributed across multiple storage devices. By way of example, a software module may be loaded into RAM from a hard drive when a triggering event occurs. During execution of the software module, the processor may load some of the instructions into cache to increase access speed. One or more cache lines may then be loaded into a general register file for execution by the processor. When referring to the functionality of a software module below, it will be understood that such functionality is implemented by the processor when executing instructions from that software module.

Also, any connection is properly termed a computer-readable medium. For example, if the software is transmitted from a website, server, or other remote source using a coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL) , or wireless technologies such as infrared (IR) , radio, and microwave, then the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, and microwave are included in the definition of medium. Disk and disc, as used herein, include compact disc (CD) , laser disc, optical disc, digital versatile disc (DVD) , floppy disk, and

disc where disks usually reproduce data magnetically, while discs reproduce data optically with lasers. Thus, in some aspects computer-readable media may comprise non-transitory computer-readable media (e.g., tangible media) . In addition, for other aspects computer-readable media may comprise transitory computer- readable media (e.g., a signal) . Combinations of the above should also be included within the scope of computer-readable media.

Thus, certain aspects may comprise a computer program product for performing the operations presented herein. For example, such a computer program product may comprise a computer-readable medium having instructions stored (and/or encoded) thereon, the instructions being executable by one or more processors to perform the operations described herein. For example, instructions for performing the operations described herein.

Further, it should be appreciated that modules and/or other appropriate means for performing the methods and techniques described herein can be downloaded and/or otherwise obtained by a user terminal and/or base station as applicable. For example, such a device can be coupled to a server to facilitate the transfer of means for performing the methods described herein. Alternatively, various methods described herein can be provided via storage means (e.g., RAM, ROM, a physical storage medium such as a compact disc (CD) or floppy disk, etc. ) , such that a user terminal and/or base station can obtain the various methods upon coupling or providing the storage means to the device. Moreover, any other suitable technique for providing the methods and techniques described herein to a device can be utilized.

It is to be understood that the claims are not limited to the precise configuration and components illustrated above. Various modifications, changes and variations may be made in the arrangement, operation and details of the methods and apparatus described above without departing from the scope of the claims.

Claims

A method for wireless communication, comprising:

partitioning information bits into first and second pluralities of information bits;

encoding the first plurality of information bits information bits to obtain a first set of coded bits;

encoding the second plurality of the information bits with a Reed-Solomon encoder to obtain a second set of bits;

combining the first set of coded bits and the second set of coded bits into a symbol; and

transmitting the symbol to a receiving device.
The method of claim 1, wherein the first plurality of information bits corresponds to an inner constellation and the second plurality of information bits corresponds to an outer constellation.
The method of claim 2, wherein the inner constellation comprises M-quadrature amplitude modulation (QAM) , M being equal to 2 ^m, and m being an integer greater than or equal to 1; and

the outer constellation comprises N-quadrature amplitude modulation (QAM) , N being equal to 2 ⁿ, and n being an integer greater than or equal to 1.
The method of claim 2 or 3, wherein the second set of coded bits has a higher reliability than the first set of coded bits.
The method of any of claims 1 to 4, wherein the first set of coded bits are encoded using a foreward error correction code.
The method of claims 1 to 5, wherein combining maps bits from the second set of coded bits to positions more likely to have errors due to channel fade.
The method of any earlier claim, further comprising mapping the symbols to OFDM resources.
The method of claim 7, wherein symbols are mapped to OFDM resources first by time domain index then by frequency domain index.
A method for wireless communication, comprising:

receiving a modulated symbol from a transmitting device;

demodulating a first portion of the modulated symbol to obtain a first set of coded bits;

decoding the first set of coded bits to obtain a first set of information bits based at least in part on an encoder used at the transmitting device;

demodulating a second portion of the modulated symbol to obtain a second set of coded bits;

decoding the second set of coded bits to obtain a second set of information bits based at least in part on a Reed-Solomon encoder used at the transmitting device; and

combining the first set of information bits and the second set of information bits.
The method of claim 9, wherein the first portion of the modulated symbol corresponds to an inner constellation and the second portion of the modulated symbol corresponds to an outer constellation.
The method of claim 10, wherein the inner constellation comprises M-quadrature amplitude modulation (QAM) , M being equal to 2 ^m, and m being an integer greater than or equal to 1; and

the outer constellation comprises N-quadrature amplitude modulation (QAM) , N being equal to 2 ⁿ, and n being an integer greater than or equal to 1.
The method of claim 10 or 11, wherein the second set of coded bits has a higher reliability than the first set of coded bits.
The method of any of claims 9 to 12, wherein the first set of coded bits are encoded using a forward error correction code.
Apparatus for wireless communication, comprising:

means for partitioning information bits into first and second pluralities of information bits;

means for encoding the first plurality of information bits information bits to obtain a first set of coded bits;

means for encoding the second plurality of the information bits with a Reed-Solomon encoder to obtain a second set of bits;

means for combining the first set of coded bits and the second set of coded bits into a symbol; and

means for transmitting the symbol to a receiving device.
The apparatus of claim 14, wherein the first plurality of information bits corresponds to an inner constellation and the second plurality of information bits corresponds to an outer constellation.
The apparatus of claim 15, wherein the inner constellation comprises M-quadrature amplitude modulation (QAM) , M being equal to 2 ^m, and m being an integer greater than or equal to 1; and

the outer constellation comprises N-quadrature amplitude modulation (QAM) , N being equal to 2 ⁿ, and n being an integer greater than or equal to 1.
The apparatus of claim 14 or 15, wherein the second set of coded bits has a higher reliability than the first set of coded bits.
The apparatus of any of claims 14 to 17, wherein the first set of coded bits are encoded using a foreward error correction code.
The apparatus of claims 14 to 18, wherein combining maps bits from the second set of coded bits to positions more likely to have errors due to channel fade.
The apparatus of any of claims 14 to 19 claim, further comprising means for mapping the symbols to OFDM resources.
The apparatus of claim 20, wherein symbols are mapped to OFDM resources first by time domain index then by frequency domain index.
Apparatus for wireless communication, comprising:

means for receiving a modulated symbol from a transmitting device;

means for demodulating a first portion of the modulated symbol to obtain a first set of coded bits;

means for decoding the first set of coded bits to obtain a first set of information bits based at least in part on an encoder used at the transmitting device;

means for demodulating a second portion of the modulated symbol to obtain a second set of coded bits;

means for decoding the second set of coded bits to obtain a second set of information bits based at least in part on a Reed-Solomon encoder used at the transmitting device; and

means for combining the first set of information bits and the second set of information bits.
The apparatus of claim 22, wherein the first portion of the modulated symbol corresponds to an inner constellation and the second portion of the modulated symbol corresponds to an outer constellation.
The apparatus of claim 23, wherein the inner constellation comprises M-quadrature amplitude modulation (QAM) , M being equal to 2 ^m, and m being an integer greater than or equal to 1; and

the outer constellation comprises N-quadrature amplitude modulation (QAM) , N being equal to 2 ⁿ, and n being an integer greater than or equal to 1.
The apparatus of any of claim 22 to 24, wherein the second set of coded bits has a higher reliability than the first set of coded bits.
The apparatus of any of claims 22 to 25, wherein the first set of coded bits are encoded using a forward error correction code.
An apparatus for wireless communication, comprising:

a processing system configured to

partition information bits into first and second pluralities of information bits,

encode the first plurality of information bits information bits to obtain a first set of coded bits,

encode the second plurality of the information bits with a Reed-Solomon encoder to obtain a second set of bits,

combine the first set of coded bits and the second set of coded bits into a symbol; and

a transmitter configured to transmit the symbol.
An apparatus for wireless communication, comprising:

a receiver for receiving a modulated symbol from a transmitting device; and

a processing system configured to

demodulate a first portion of the modulated symbol to obtain a first set of coded bits,

decode the first set of coded bits to obtain a first set of information bits based at least in part on an encoder used at the transmitting device,

demodulate a second portion of the modulated symbol to obtain a second set of coded bits,

decode the second set of coded bits to obtain a second set of information bits based at least in part on a Reed-Solomon encoder used at the transmitting device; and

combine the first set of information bits and the second set of information bits.
A computer-readable medium having instructions stored thereon to cause an apparatus to:

partition information bits into first and second pluralities of information bits,

encode the first plurality of information bits information bits to obtain a first set of coded bits,

encode the second plurality of the information bits with a Reed-Solomon encoder to obtain a second set of bits,

combine the first set of coded bits and the second set of coded bits into a symbol; and

transmit the symbol.
A computer-readable medium having instructions stored thereon to cause an apparatus to:

receive a modulated symbol from a transmitting device;

demodulate a first portion of the modulated symbol to obtain a first set of coded bits,

decode the first set of coded bits to obtain a first set of information bits based at least in part on an encoder used at the transmitting device,

demodulate a second portion of the modulated symbol to obtain a second set of coded bits,

decode the second set of coded bits to obtain a second set of information bits based at least in part on a Reed-Solomon encoder used at the transmitting device; and

combine the first set of information bits and the second set of information bits.