REFERENCE TO RELATED APPLICATION

[0001] This patent application claims priority to United States Provisional

Patent Application Serial No. 61/187573 that was filed on June 16, 2009 and assigned to the assignee hereof, and is hereby expressly incorporated by reference herein.

BACKGROUND

Field

[0002] The present work relates generally to wireless communications systems, methods, computer program products and devices, and more specifically to apparatus and methods for Bluetooth (BT) and Wireless Local Area Network (WLAN) coexistence. More particularly, the present work relates to dynamic and dual antenna Bluetooth and WLAN coexistence.

Background

[0003] In many telecommunication systems, communications networks are used to exchange messages among several interacting elements which are separated in space. There are many types of networks which may be classified in different aspects. In one example, the geographic scope of the network could be over a wide area, a metropolitan area, a local area, or a personal area, and the corresponding networks would be designated as wide area network (WAN), metropolitan area network (MAN), local area network (LAN), or personal area network (PAN). Networks also differ in the switching/routing technique used to interconnect the various network nodes and devices (e.g. circuit switching vs. packet switching), in the type of physical media employed for waveform propagation (e.g. wired vs. wireless), or in the set of communication protocols used (e.g. Internet protocol suite, SONET (Synchronous Optical Networking), Ethernet, etc.).

[0004] One important characteristic of communications networks is the choice of wired or wireless media for the transmission of electrical signals among the constituents of the network. In the case of wired networks, tangible physical media such as copper wire, coaxial cable, fiber optic cable, etc. are employed to propagate guided electromagnetic waveforms which carry message traffic over a distance. Wired networks are a traditional form of communications networks and are typically favored for interconnection of fixed network elements or for bulk data transfer. For example, fiber optic cables are often the preferred transmission media for very high throughput transport applications over long distances between large network hubs, for example, bulk data transport across or between continents over the Earth's surface. [0005] On the other hand, in many cases, wireless networks are preferred when the network elements are mobile with dynamic connectivity or if the network architecture is formed in an ad hoc, rather than fixed, topology. Wireless networks employ intangible physical media in an unguided propagation mode using electromagnetic waves in the radio, microwave, infrared, optical, etc. frequency bands. Wireless networks have the distinct advantage of facilitating user mobility and rapid field deployment compared to fixed wired networks. However, usage of wireless propagation requires significant active resource management among the network users and high levels of mutual coordination and cooperation for compatible spectrum utilization. [0006] For example, popular wireless network technologies include Bluetooth

(BT) and wireless local area networks (WLAN). Bluetooth and WLAN are both wireless communication protocols that are designed to provide connectivity to devices. Bluetooth and WLAN operate in the same frequency band.

[0007] Bluetooth is widely used to implement a personal area network (PAN) over very short distances, typically for a coverage area of a few meters radius, as an alternative to wired interconnection among local components. In one example, Bluetooth may be used to connect personal computers, personal digital assistants (PDA), mobile phones, wireless headsets, etc. Alternatively, a WLAN may be used to interconnect nearby devices together, employing widely used networking protocols such as WiFi or, more generally, a member of the IEEE 802.11 wireless protocol family. [0008] One issue with wireless network technologies is that they often share the same frequency band for transmission. Thus, co-channel interference is a problem that must be actively managed. For example, both Bluetooth and WLAN systems may use the same unlicensed Industrial, Scientific, and Medical (ISM) spectral band located around two and four tenths GigaHertz (2.4 GHz). In one example, mobile devices may share a cost-effective common antenna which accesses both wireless technologies. To support user scenarios with simultaneous BT and WLAN operation, time division multiple access (TDMA) coexistence algorithms are required. Thus, a coexistence algorithm is needed to arbitrate usage between Bluetooth and WLAN access technologies for co-located wireless devices.

[0009] In common wireless practice, packet traffic arbitration (PTA) is used to implement coexistence among different access technologies. In one example, the PTA may be implemented through two, three or four wire interfaces between BT and WLAN electronic chips in a wireless device. Each access technology makes channel requests for individual packets with an optional priority indication for that request. [0010] The PTA makes decisions on who gets access when both access technologies contend for a channel request simultaneously. This mechanism may prevent some collisions between the technologies for transmit traffic but does not prevent collisions between receive traffic. A collision is a conflict when two or more data sources attempt to transmit over the same medium at the same time. To prevent receive traffic collisions, the remote device transmissions are controlled by a protocol. In one example, if the wireless device is a BT master, it can control the BT receptions by choosing when to transmit polling frames to the remote device. [0011] In another example, a device which follows a WLAN protocol is typically a client communicating with a wireless access point (AP). The AP transmissions may be controlled using existing power save operation and protection features. In one example, these features include transitioning in and out of power save mode, sending a power save mode poll to request a single packet, and requesting a send or clear signal to send packets to prevent other transmissions. Existing devices can use one of these WLAN techniques without having any information regarding the BT link. [0012] There is a need in the art for a method and apparatus that is capable of effectively and efficiently arbitrating usage between Bluetooth and WLAN access technologies for co-located wireless devices.

SUMMARY

[0013] The present work discloses a state level arbitration method that effectively and efficiently arbitrates concurrent usage between WLAN and Bluetooth access technologies for co-located wireless devices. The present work also discloses a state level arbiter that determines state and relevant parameters of a WLAN module and of a Bluetooth module of a wireless transceiver unit. The state level arbiter uses the state and relevant parameters to determine which access technology (WLAN or Bluetooth) or combination of access technologies (WLAN or Bluetooth) will provide the best concurrent performance for wireless transmissions at a given time for specific Bluetooth states and WLAN states.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Various aspects of a wireless communications system of the present work are illustrated by way of example, and not by way of limitation, in the accompanying drawings, wherein

[0015] FIG. 1 illustrates a diagram of a portion of wireless communications transceiver unit that comprises a Bluetooth transmission (Tx) unit, and a Bluetooth receive (Rx) unit, and a WLAN receive (Rx) unit, and a WLAN transmission (Tx) unit and a first antenna that is capable of being selectively coupled to the four units. FIG. 1 illustrates that the transceiver unit also comprises a WLAN diversity receive (DRx) unit and a second antenna that is capable of being selectively coupled to the WLAN transmission (Tx) unit and to the WLAN diversity receiver (DRx) unit;

[0016] FIG. 2 illustrates a diagram of a portion of a wireless communications transceiver unit that comprises a WLAN module, and a Bluetooth module, and a state level arbiter (SLA) in accordance with the principles of the present work;

[0017] FIG. 3 illustrates a flow chart showing the steps of an advantageous embodiment of a method of the present work for performing state level arbitration in a transceiver unit that comprises both a WLAN module and a Bluetooth module;

[0018] FIG. 4 illustrates a first schematic diagram showing elements of a state level arbitration algorithm of the present work;

[0019] FIG. 5 illustrates a second schematic diagram showing elements of a state level arbitration algorithm of the present work;

[0020] FIG. 6 illustrates a diagram of programmable diplexer in accordance with the principles of the present work for providing radio frequency (RF) isolation in which a single antenna is used; [0021] FIG. 7 illustrates a diagram of another programmable diplexer in accordance with the principles of the present work for providing radio frequency (RF) isolation in which a single antenna is used; and

[0022] FIG. 8 illustrates a communications system in which principles according to the present work may be incorporated.

DETAILED DESCRIPTION

[0023] The word "exemplary" is used herein to mean "serving as an example, instance, or illustration." Any embodiment described herein as "exemplary" is not necessarily to be construed as preferred or advantageous over other embodiments. [0024] The present work discloses a BT/WLAN coexistence solution that uses a state level arbiter (SLA) in a wireless device that communicates with both Bluetooth (BT) and WLAN access technologies. As will be more fully described, the state level arbiter (SLA) determines the state and relevant parameters of both the Bluetooth access technology and the WLAN access technology. The state level arbiter (SLA) uses the state and relevant parameters to determine which technique (Bluetooth or WLAN) or combination of the two techniques will provide the best performance for the specific Bluetooth states and WLAN states at any given time.

[0025] In Bluetooth (BT), there are two connectivity types for transporting data over time slots in a time division scheme. The two types are asynchronous connectionless link (ACL) and synchronous connection oriented (SCO). ACL is a packet-oriented transmission mode without usage of reserved time slots. SCO, in contrast, is a circuit-oriented transmission mode which uses reserved time slots. [0026] For example, when the BT state is in ACL sniff mode and is only performing occasional activities and when the WLAN state is in an active data transmission mode, the wireless device may use the PTA to allow the BT state activity at the expense of a few missed WLAN packets. In another example, when the BT state is in a SCO mode and the WLAN state is in an active data transmission mode, the wireless device may indicate to the WLAN AP that the device is in power save mode and may use power save polling frames during the gap between BT SCO activities to retrieve WLAN data. [0027] In another example, when the BT state is in ACL data mode and the

WLAN state is in an active data transmission mode, the state level arbiter (SLA) will adaptive Iy allocate time periods to the BT and WLAN states. The BT activity is controlled by simply enabling or disabling the BT state. The WLAN activity is controlled by transitioning in and out of power save mode.

[0028] For cost and other reasons, typical devices share a common antenna for the two technologies. In order to support user scenarios where BT and WLAN operate simultaneously from a user perspective, time division multiple access (TDMA) algorithms that permit BT and WLAN to coexist are implemented. [0029] However, performance improvement can be achieved by running the systems concurrently using separate antennas for BT and WLAN and designing the BT and WLAN RF circuits to accommodate the presence of a strong interfering technology within the same device. Additionally, changes in BT and WLAN power control responsive to the transmit power levels and receive power levels of each technology can be implemented to improve the range of conditions over which dual antenna concurrency is possible. The state level arbiter of the present work implements a high level algorithm to switch between dual antenna concurrency and traditional TDMA techniques responsive to the signal conditions and performance.

[0030] FIG. 1 illustrates a diagram of a portion of wireless communications transceiver unit 100 that comprises a Bluetooth transmission (Tx) unit 105, and a Bluetooth receive (Rx) unit 110, and a WLAN receive (Rx) unit 115, and a WLAN transmission (Tx) unit 120 and a first antenna 125 that is capable of being selectively coupled to the four units (105, 110, 115, 120). FIG. 1 illustrates that the transceiver unit 100 also comprises a WLAN diversity receive (DRx) unit 130 and a second antenna 175 that is capable of being selectively coupled to the WLAN transmission (Tx) unit 120 and to the WLAN diversity receiver (DRx) unit 130.

[0031] As shown in FIG. 1, the first antenna 125 may be coupled to the BT transmission (Tx) unit 105 through switch 135 and power amplifier 140. The first antenna 125 may also be coupled to the Bluetooth receive (Rx) unit 110 and to the WLAN receive (Rx) unit 115 through switch 145 and low noise amplifier (LNA) 150. The first antenna 125 may also be coupled to the WLAN transmission (Tx) unit 120 through switch 155 and power amplifier 160.

[0032] Two additional switches (switch 165 and switch 170) are required to support two antenna diversity. Second antenna 175 can be coupled to the WLAN receive (Rx) unit 120 through switch 165 and power amplifier 160. Second antenna 175 can also be coupled to the WLAN diversity receive (DRx) unit 130 through switch 170 and low noise amplifier (LNA) 180. The switches (135, 145, 155, 165 and 170) of transceiver unit 100 are connected to and controlled by the state level arbiter (SLA) (not shown in FIG. 1).

[0033] Transceiver unit 100 may be operated with concurrent Bluetooth and

WLAN systems using the first antenna 125 as the primary antenna 125 and the second antenna 175 as the diversity antenna 175. In this configuration, the primary antenna 125 is used solely for the Bluetooth transmission (Tx) signals from the Bluetooth transmission (Tx) unit 105 and the Bluetooth receive (Rx) signals from the Bluetooth receive (Rx) unit 110. The diversity antenna 175 is used for the WLAN transmission (Tx) signals from the WLAN transmission (Tx) unit 120 and the WLAN diversity receive (DRx) signals from the WLAN diversity receive (DRx) unit 130. [0034] During concurrent operation with the two antennas (125 and 175),

Bluetooth will use the primary antenna 125 and WLAN will use the diversity antenna 175. The WLAN diversity receive (DRx) unit 130 will use the diversity low noise amplifier (LNA) 180. Transmissions from the WLAN transmission (Tx) unit 120 will be routed to the diversity antenna 175 through power amplifier (PA) 160 and switch 165. The WLAN diversity receive (DRx) path baseband (BB) filter will increase from a third order to a fifth order. This will require an increase in area cost of about two tenths of a square millimeter (~0.2 mm ² ). The automatic gain control (AGC) algorithms will be modified but the modifications will have no hardware impact.

[0035] FIG. 2 illustrates a diagram of a portion of wireless communications transceiver unit 100 that comprises a WLAN module 210, and a Bluetooth module 220, and a state level arbiter (SLA) 230 in accordance with the principles of the present work. The various circuit components that comprise the WLAN circuitry in transceiver unit 100 are generally designated as WLAN module 210. Similarly, the various circuit components that comprise the Bluetooth circuitry in transceiver unit 100 are generally designated as Bluetooth module 220. The Bluetooth module 220 is coupled to the WLAN module 210 and is capable of communicating state information to the WLAN module 220 through signal lines 215.

[0036] The state level arbiter (SLA) 230 comprises a microprocessor 240.

A user interface unit 250 is connected to the microprocessor 240. The user interface unit 250 allows user access to the microprocessor 240 of the state level arbiter (SLA) 230. The microprocessor 240 comprises a memory 260. The memory 260 comprises state level arbiter algorithm software 270 and an operating system 280. The microprocessor 240 of the state level arbiter (SLA) 230 receives information from the WLAN module 210 and from the Bluetooth module 220 via signal lines that are not shown in FIG. 2. The microprocessor 240 of the state level arbiter (SLA) 230 sends control signals to the WLAN module 210 and to the Bluetooth module 220 via control signal lines that are also not shown in FIG. 2.

[0037] Together the microprocessor 240 and the state level arbiter algorithm software 270 comprise a state level arbiter processor that is cable of carrying out the state level arbiter function for a transceiver unit 100 that comprises both a WLAN module 210 and a Bluetooth module 220. The state level arbiter algorithm software 270 carries out the method of the present work to select for a wireless transceiver the better access technology (WLAN or Bluetooth) or combination of the two access technologies (WLAN or Bluetooth) to perform a better concurrent transmission performance for specific Bluetooth states and WLAN states.

[0038] The wireless transceiver unit 100 is concurrently running two access technologies (Bluetooth and WLAN) for two different applications. The state level arbiter processor selects the appropriate access technology (or combination of the two access technologies) to provide the better concurrent performance in order to provide the best possible overall user experience. For example, assume that a first one of the access technologies is performing a web page download and that the second one of the access technologies is performing voice transmissions. Interrupting the voice transmissions is more detrimental than delaying a web page download. Therefore, the access technology that is performing the voice transmissions is given priority. This provides the better concurrent performance with respect to the two access technologies. [0039] For another example, assume that a first one of the access technologies is attempting to establish a connection and that the second one of the access technologies is performing some other task. If priority is given to the second one of the access technologies, then the user will experience a connection failure. Therefore, the access technology that is attempting to establish a connection is given priority. This provides the better concurrent performance with respect to the two access technologies. [0040] The state level arbiter algorithm software 270 comprises a computer program product for performing the method of the present work. The computer program product comprises a computer-readable medium that comprises code for carrying out computer instructions to perform the method. The computer program product is shown schematically in FIG. 2 as a computer-readable disk 290. The computer-readable disk 290 is merely illustrative of one type of computer program product. The computer program product may also comprise other types of computer-readable media such as magnetic tapes, hard drives, flash drives, and similar products.

[0041] FIG. 3 illustrates a flow chart 300 showing the steps of an advantageous embodiment of a method of the present work for performing state level arbitration in a wireless transceiver unit 100 that comprises both a WLAN module 210 and a Bluetooth module 220. In the first step a state level arbiter 230 is provided in a wireless transceiver unit 100 that comprises both a WLAN module 210 and a Bluetooth module 220 (step 310). The state level arbiter 230 determines the state and relevant parameters of the WLAN module 210 and of the Bluetooth module 220 (step 320). [0042] The state level arbiter 230 uses the state and relevant parameters to determine which access technology (WLAN or Bluetooth) or combination of access technologies (WLAN or Bluetooth) will provide the best concurrent performance at a given time (step 330). The state level arbiter 230 selects the better of the two access technologies (WLAN or Bluetooth) or the best combination of the two access technologies (WLAN or Bluetooth) to perform wireless transmissions for specific Bluetooth states and WLAN states (step 340). [0043] There are three main approaches to establishing WLAN-B luetooth coexistence in a wireless transmitter. The first approach is time division multiplexing (TDM). In time division multiplexing (TDM) media access control (MAC) techniques are employed to allow only one system (either WLAN or Bluetooth) to operate at any given time. Packet traffic arbitration (PTA) is employed to control the transmission of the data packets. IEEE 802.11 features are used to control the timing of access point (AP) transmissions. In time division multiplexing (TDM) the maximum throughput that is possible is dictated by the percentage of time that a system (either WLAN or Bluetooth) has the transmission channel.

[0044] The second approach to establishing WLAN-Bluetooth coexistence in a wireless transmitter is Concurrency with Radio Frequency (RF) Isolation. This approach includes (1) separation in frequency, and (2) the reduction of interference between the transmitter of one technology and the receiver of the other technology. In one application the Concurrency with RF Isolation method is carried out using a single antenna and a programmable diplexer that switches the single antenna between the WLAN technology and the Bluetooth technology. In another application the Concurrency with RF Isolation method is carried out using a two antennas (sometimes referred to as a dual antenna) with good radio frequency (RF) isolation. Full standalone throughput can be achieved when the radio frequency (RF) isolation is sufficient for the given signal conditions.

[0045] The third approach to establishing WLAN-Bluetooth coexistence in a wireless transmitter is combines time division multiplexing (TDM) with Radio Frequency (RF) Isolation. This combined approach provides the best solution in the long run. Time division multiplexing (TDM) will be used when advanced frequency hopping (AFH) is not possible or when the frequencies that are used by advanced frequency hopping (AFH) overlap with the WLAN frequencies. Time division multiplexing (TDM) will also be used when the transmit power of one technology is strong and the receive power of the other technology is weak so that the resulting radio frequency (RF) isolation is insufficient.

[0046] Radio frequency (RF) isolation will be used in the third approach for the times when time division multiplexing (TDM) is not selected for use. The performance of the radio frequency (RF) isolation method is quantified by the range of practical conditions where the two systems (WLAN and Bluetooth) can operate at full concurrency.

[0047] As previously described, the state level arbiter 230 uses the state and relevant parameters to determine which access technology (WLAN or Bluetooth) or combination of access technologies (WLAN or Bluetooth) will provide the best performance at a given time. The state level arbiter 230 performs WLAN-Bluetooth state arbitration in accordance with the priority decisions that are set forth in the schematic diagrams in FIG. 4 and FIG. 5.

[0048] FIG. 4 illustrates a first schematic diagram showing elements of a state level arbitration algorithm of the present work. The diagram shows the priority decisions of the WLAN-Bluetooth state arbitration. For example, when the Bluetooth system sends a Bluetooth Inquiry and the state level arbiter 230 determines that the WLAN is active, the state level arbiter 230 will give priority to the Bluetooth system and suspend the WLAN activity. The text "See next slide" in the first schematic diagram means that reference should be made to the second schematic diagram that is shown in FIG. 5.

[0049] FIG. 6 illustrates a diagram of programmable diplexer 600 in accordance with the principles of the present work for providing radio frequency (RF) isolation in which a single antenna is used. The programmable diplexer 600 comprises a Bluetooth module 610 and a WLAN module 615. As shown in FIG. 6, the WLAN module 615 comprises a WLAN Libra System on a Chip (SoC) module 620. The Bluetooth module 610 provides state information to a decoder 625 in the WLAN Libra SoC module 620 through signal lines 630. In one advantageous embodiment, signal lines 630 comprise a three (3) pin coexistence interface in which a first pin carries a BT ACTIVE signal and a second pin carries a TX CONFIRM signal and a third pin carries a BT PRIORITY signal.

[0050] The Bluetooth transmission (Tx) path comprises quadrature mixer TX

632, power amplifier 634, match unit 636, single pole double throw (SP2T) switch 638, balun and match unit 640, single pole triple throw (SP3T) antenna switch 642, band pass filter (BPF) 644 and antenna 125. The Bluetooth receive (Rx) path comprises antenna 125, band pass filter (BPF) 644, single pole triple throw (SP3T) antenna switch 642, balun and match unit 640, single pole double throw (SP2T) switch 638, match unit 646, low noise amplifier (LNA) 648 and quadrature mixer RX 650. [0051] The WLAN transmission (Tx) path comprises quadrature mixer TX 652, power amplifier 654, balun and match unit 656, single pole triple throw (SP3T) antenna switch 642, band pass filter (BPF) 644 and antenna 125. The WLAN receive (Rx) path comprises antenna 125, band pass filter (BPF) 644, single pole triple throw (SP3T) antenna switch 642, match unit 658, low noise amplifier (LNA) 660, balun and match unit 662 and quadrature mixer RX 664.

[0052] The operations of single pole double throw (SP2T) switch 638 and the operations of single pole triple throw (SP3T) antenna switch 642 are controlled by control signals from the state level arbiter 230. The control signals from the state level arbiter 230 to switch 638 and to switch 642 are carried by control signal lines that are not shown in FIG. 6.

[0053] FIG. 7 illustrates a diagram of another programmable diplexer 700 in accordance with the principles of the present work for providing radio frequency (RF) isolation in which a single antenna is used. The programmable diplexer 700 comprises a Bluetooth module 710 and a WLAN module 715. The Bluetooth module 710 provides state information to a decoder 725 in the WLAN module 715 through signal lines 730. In one advantageous embodiment, signal lines 730 comprise a three (3) pin coexistence interface in which a first pin carries a BT ACTIVE signal and a second pin carries a TX CONFIRM signal and a third pin carries a BT PRIORITY signal. [0054] The Bluetooth transmission (Tx) path comprises quadrature mixer TX

732, power amplifier 734, match unit 736, single pole double throw (SP2T) switch 738, balun and match unit 740, first micro-electromechanical (MEMs) device notch 744, band pass filter (BPF) 746 and antenna 125. The Bluetooth receive (Rx) path comprises antenna 125, band pass filter (BPF) 746, first micro-electromechanical (MEMs) device notch 744, balun and match unit 740, single pole double throw (SP2T) switch 738, match unit 748, low noise amplifier (LNA) 750 and quadrature mixer RX 752. [0055] The WLAN transmission (Tx) path comprises quadrature mixer TX 754, power amplifier 756, balun and match unit 758, power amplifier 760, single pole double throw (SP2T) switch 762, second micro-electromechanical (MEMs) device notch 764, band pass filter (BPF) 746 and antenna 125. The WLAN receive (Rx) path comprises antenna 125, band pass filter (BPF) 746, second micro-mechanical (MEMs) device notch 764, single pole double throw (SP2T) switch 762, balun and match unit 766, low noise amplifier (LNA) 768, and quadrature mixer RX 770. [0056] The operations of single pole double throw (SP2T) switch 738 and the operations of single pole double throw (SP2T) switch 762 are controlled by control signals from the state level arbiter 230. The control signals from the state level arbiter 230 to switch 738 and to switch 762 are carried by control signal lines that are not shown in FIG. 6.

[0057] In addition, state level arbiter 230 controls the operation of the first micro-electromechanical (MEMs) device notch 744 and the operation of the second micro-electromechanical (MEMs) device notch 764. Each of the micro- electromechanical (MEMs) device notches (744 and 764) is programmable by the state level arbiter 230. This means that the programmable diplexer 700 is totally reconfigurable if the WLAN band of operation is changed. In the case of Bluetooth or WLAN operation, one or the other, the MEMs device notch in the path that is not used will be programmed to be high impedance. Programming a MEMs device notch to be high impedance can be achieved in one of two ways.

[0058] Method One. In the case of WLAN only, the MEMs device notch in the

Bluetooth path can remain unchanged as it would already be high impedance. It may be possible, however, to make the value of impedance even higher as in this case, there is no requirement on a low insertion loss for the Bluetooth (i.e., the Bluetooth is off). In the case of Bluetooth only, the reverse is true.

[0059] Method Two. The MEMs device notch can be programmed to be much wider and deeper to that it is higher impedance and a better open circuit. [0060] The basis behind the programming of a MEMs device notch in single operation is to make the programmable diplexer 700 operate more like a switch. Having the MEMs device notch operate more like a switch is single operation means that time share operation may also be used. [0061] FIG. 8 illustrates a communications system 800 in which principles according to the present work may be incorporated. In general, the system 800 creates and broadcasts multimedia content across various networks to a large number of mobile subscribers. The communications system 800 includes any number of content providers 802, a content provider network 804, a broadcast network 806, and a wireless access network 808. The communications system 800 is also shown with a number of devices 810 used by mobile subscribers to receive multimedia content. These devices 810 include a mobile telephone 812, a laptop computer 814, and a person digital assistant (PDS) 816. The devices 810 illustrate just some of the devices that are suitable for use in the communications system 800. It should be noted that although three devices are shown in FIG. 8, virtually any number of analogous devices or types of devices are suitable for use in the communications system 800, as would be apparent to those skilled in the art.

[0062] The content providers 802 provide content for distribution to mobile subscribers in the communications system 800. The content may include video, audio, multimedia content, clips, real-time and non real-time content, scripts, programs, data or any other type of suitable content. The content providers 802 provide content to the content provider network for wide-area or local-area distribution.

[0063] The content provider network 804 comprises any combination of wired and wireless networks that operate to distribute content for delivery to mobile subscribers. In the example illustrated in FIG. 8, the content provider network 804 distributes content through a broadcast network 806. The broadcast network 806 comprises any combination of wired and wireless proprietary networks that are designed to broadcast high quality content. These proprietary networks may be distributed throughout a large geographic region to provide seamless coverage to mobile devices. Typically, the geographic region will be divided into sectors with each sector providing access to wide-area and local-area content.

[0064] The content provider network 804 may also include a content server

(not shown) for distribution of content through a wireless access network 808. The content server communicates with a base station controller (BSC) (not shown) in the wireless access network 808. The BSC may be used to manage and control any number of base transceiver stations (BTSs) (not shown) depending on the geographic reach of the wireless access network 808. The BTSs provide access to wide-area and local-area for the various devices 810.

[0065] The multimedia content broadcast by the content providers 802 include one or more services. A service is an aggregation of one or more independent data components. Each independent data component of a service is called a flow. By way of example, a cable news service may include three flows: a video flow, an audio flow, and a control flow.

[0066] Services are carried over one or more logical channels. In Forward Link

Only (FLO) Air Interface applications, a logical channel is often referred to as a Multicast Logical Channel (MLC). A logical channel may be divided into multiple logical sub-channels. These logical sub-channels are called streams. Each flow is carried in a single stream. The content for a logical channel is transmitted through the various networks in a physical frame. In Forward Link Only (FLO) Air Interface applications, the physical frame is often referred to as a superframe.

[0067] The air interface used to transmit the physical frames to the various devices 810 shown in FIG. 8 may vary depending on the specific application and the overall design constraints. In general, communications systems employing Forward Link Only (FLO) technology utilize Orthogonal Frequency Division Multiplexing (OFDM), which is also utilized by Digital Audio Broadcasting (DAB), Terrestrial Digital Video Broadcasting (DVB-T), and Terrestrial Integrated Services Digital Broadcasting (ISDB-T). OFDM is a multi-carrier modulation technique that effectively partitions the overall system bandwidth into multiple (N) sub-carriers. These sub- carriers, which are also referred to as tones, bins, frequency channels, etc., are spaced apart at precise frequencies to provide orthogonality. Content may be modulated onto the sub-carriers by adjusting each sub-carrier's phase, amplitude or both. Typically, quadrature phase shift keying (QPSK) or quadrature amplitude modulation (QAM) is used, but other modulation schemes may also be used.

[0068] Those of skill in the art would understand that information and signals may be represented using any of a variety of different technologies and techniques. For example, data, instructions, commands, information, signals, bits, symbols, and chips that may be referenced throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or particles, optical fields or particles, or any combination thereof.

[0069] Those of skill would further appreciate that the various illustrative logical blocks, modules, circuits, and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware, computer software, or combinations of both. To clearly illustrate this interchangeability of hardware and software, various illustrative components, blocks, modules, circuits and steps have been described above generally in terms of their functionality. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the overall system. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present work.

[0070] The various illustrative logical blocks, modules, and circuits described in connection with the embodiments disclosed herein 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, 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 conventional 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.

[0071] The steps of a method or algorithm described in connection with the embodiments disclosed herein may be embodied directly in hardware, in a software module executed by a processor, or in a combination of the two. A software module may reside in RAM memory, flash memory, ROM memory, EPROM memory, EEPROM memory, registers, hard disk, a removable disk, a CD-ROM, or any other form of storage medium known in the art. An exemplary storage medium is coupled to the 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. The processor and the storage medium may reside on an ASIC. The ASIC may reside in a user terminal. In the alternative, the processor and the storage medium may reside as discrete components in a user terminal. [0072] The description set forth in connection with the appended drawings is intended as a description of various aspects of the present disclosure and is not intended to represent the only aspects in which the present disclosure may be practiced. Each aspect described in this disclosure is provided merely as an example or illustration of the present disclosure, and should not necessarily be construed as preferred or advantageous over other aspects. The description includes specific details for the purpose of providing a thorough understanding of the present disclosure. However, it will be apparent to those skilled in the art that the present disclosure may be practiced without these specific details. In some instances, well-known structures and devices are shown in block diagram form in order to avoid obscuring the concepts of the present disclosure. Acronyms and other descriptive terminology may be used merely for convenience and clarity and are not intended to limit the scope of the disclosure. [0073] While for purposes of simplicity of explanation, the methodologies are shown and described as a series of acts, it is to be understood and appreciated that the methodologies are not limited by the order of acts, as some acts may, in accordance with one or more aspects, occur in different orders and/or concurrently with other acts from that shown and described herein. For example, those skilled in the art will understand and appreciate that a methodology could alternatively be represented as a series of interrelated states or events, such as in a state diagram. Moreover, not all illustrated acts may be required to implement a methodology in accordance with one or more aspects. [0074] One skilled in the art would understand that the steps disclosed in the example algorithms can be interchanged in their order without departing from the scope and spirit of the present disclosure. Also, one skilled in the art would understand that the steps illustrated in the example algorithms are not exclusive and other steps may be included or one or more of the steps in the example algorithms may be deleted without affecting the scope and spirit of the present disclosure.