Patent Publication Number: US-10772079-B2

Title: Method and system for signalling resource allocation information in an asymmetric multicarrier communication network

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) AND CLAIM OF PRIORITY 
     The present application is a continuation of application Ser. No. 14/021,953, filed Sep. 9, 2013, which claims priority to Indian Application No. 3710/CHE/2012, filed, Sep. 7, 2012, Indian Application No. 4332/CHE/2012, filed Oct. 17, 2012, and Indian Application No. 3710/CHE/2012, filed May 28, 2013, the entire disclosures of which are hereby incorporated by reference. 
    
    
     BACKGROUND 
     1. Field 
     The present disclosure relates to the field of asymmetric multicarrier system, and more particularly relates to a method and system for signaling resource allocation information in an asymmetric multicarrier communication network. 
     2. Description of Related Art 
     In the recent years, several broadband wireless technologies have been developed to meet growing number of broadband subscribers and to provide more and better applications and services. For example, the Third Generation Partnership Project 2 (3GPP2) developed Code Division Multiple Access 2000 (CDMA 2000), 1× Evolution Data Optimized (1×EVDO) and Ultra Mobile Broadband (UMB) systems. The 3rd Generation Partnership Project (3GPP) developed Wideband Code Division Multiple Access (WCDMA), High Speed Packet Access (HSPA) and Long Term Evolution (LTE) systems. The Institute of Electrical and Electronics Engineers developed Mobile Worldwide Interoperability for Microwave Access (WiMAX) systems. As more and more people become users of mobile communication systems and more and more services are provided over these systems, there is an increasing need for mobile communication system with large capacity, high throughput, lower latency and better reliability. 
     Super Mobile Broadband (SMB) system based on millimeter waves, i.e., radio waves with wavelength in range of 1 millimeter (mm) to 10 mm, corresponds to a radio frequency of 30 Gigahertz (GHz) to 300 GHz, is a candidate for next generation mobile communication technology as vast amount of spectrum is available in a millimeter Wave band. In general, an SMB network consists of multiple SMB base stations (BSs) that cover a geographic area. In order to ensure good coverage, SMB base stations need to be deployed with higher density than macro-cellular base stations. In general, SMB base stations are recommended to be deployed roughly the same site-to-site distance as microcell or pico-cell deployment in an urban environment. Typically, transmission and/or reception in an SMB system are based on narrow beams, which suppress the interference from neighboring SMB base stations and extend the range of an SMB link. However due to high path loss, heavy shadowing and rain attenuation reliable transmission at higher frequencies is one of the key issues that need to be overcome in order to make the SMB system a practical reality. 
     Lower frequencies in a cellular band having robust link characteristics can be utilized with higher frequencies in a millimeter wave (mmWave) band to overcome reliability issues in the SMB systems. In an asymmetric multicarrier communication network, a mobile station (MS) communicates with a base station using asymmetric multiband carriers consisting of at least one low frequency carrier in the cellular band and at least one high frequency carrier in the mmWave band. The primary carrier i.e., carrier operating on low frequencies and the secondary carrier i.e., carrier operating on high frequencies may be transmitted by same BS or different BS. Since the transmission characteristics of low frequency carriers in the cellular band and high frequency carriers in the mmWave band is quite different, transmission time intervals (TTIs) and the frame structures for the primary carrier and secondary carrier may not be same. An example of frame structure for a primary carrier in the cellular band where the operation is based on 3rd Generation Partnership Projects (3GPP) Long Term Evolution (LTE) Standard, and frame structure for a secondary carrier in the mmWave band is illustrated in  FIG. 1 . In frame structure for the primary carrier in the cellular band, one radio frame of length 10 milliseconds is divided into 10 radio subframes which are further sub-divided into two slots. Each slot is further composed of six or seven Orthogonal Frequency Division Multiplexing (OFDM) symbols. The BS transmits control information in the first three or the first four OFDM symbols of the first slot. The control information is intended for the both the slots of a sub frame. A control channel carrying the control information is referred to as Physical Downlink Control Channel (PDCCH) in 3GPP LTE terminology. In a frame structure for the secondary carrier in mmWave band, a radio frame of 5 milliseconds is composed of 5 subframes of 1 ms each. Each subframe is composed of P=60 slots and each slot is composed of n=4 OFDM symbols. 
     In an asymmetric multicarrier communication network, a low frequency carrier in a cellular band can be used to signal resource allocation information for high frequency carrier in an mmWave band for reliably signaling the resource allocation information. However, frame structure and transmit time intervals for high frequency carrier is different than those for low frequency carrier. 
     SUMMARY 
     Various embodiments of the present disclosure provide a method and system for signaling resource allocation information in an asymmetric multicarrier communication network. In one embodiment a MS communicates with a BS using asymmetric carriers consisting of at least one low frequency carrier (e.g., primary carriers) in a cellular band and at least one high frequency carrier secondary carriers) in a millimeter Wave band. In one embodiment, the BS allocates resources for one or more transmit time intervals in at least one of DL allocation interval of a secondary DL carrier and UL allocation interval of a secondary UL carrier for the MS, where the DL allocation interval spans one or more subframes of the secondary DL carrier and the UL allocation interval spans one or more subframes of the secondary LI carrier. The BS then transmits information regarding the allocated resources to the MS in a Packet Data Control Channel region of a subframe of the primary DL carrier. 
     Before undertaking the DETAILED DESCRIPTION OF THE DISCLOSURE below, it may be advantageous to set forth definitions of certain words and phrases used throughout this patent document: the terms “include” and “comprise,” as well as derivatives thereof, mean inclusion without limitation; the term “or,” is inclusive, meaning and/or; the phrases “associated with” and “associated therewith,” as well as derivatives thereof, may mean to include, be included within, interconnect with, contain, be contained within, connect to or with, couple to or with, be communicable with, cooperate with, interleave, juxtapose, be proximate to, be bound to or with, have, have a property of, or the like; and the term “controller” means any device, system or part thereof that controls at least one operation, such a device may be implemented in hardware, firmware or software, or some combination of at least two of the same. It should be noted that the functionality associated with any particular controller may be centralized or distributed, whether locally or remotely. Definitions for certain words and phrases are provided throughout this patent document, those of ordinary skill in the art should understand that in many, if not most instances, such definitions apply to prior, as well as future uses of such defined words and phrases. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a more complete understanding of the present disclosure and its advantages, reference is now made to the following description taken in conjunction with the accompanying drawings, in which like reference numerals represent like parts: 
         FIG. 1  illustrates a schematic representation of frame structures of a primary Downlink (DL) carrier, secondary DL carrier and a secondary Uplink (UL) carrier, according to a prior art. 
         FIG. 2A  illustrates a schematic diagram of an asymmetric multicarrier communication network where a primary carrier and a secondary carrier are transmitted by a same base station (BS). 
         FIG. 2B  illustrates a schematic diagram of another asymmetric multicarrier communication network where a primary carrier and a secondary carrier are transmitted by different BSs. 
         FIG. 3  illustrates a flowchart for a method of allocating resources to a mobile station (MS), according to one embodiment. 
         FIG. 4A  illustrates a flowchart for a method of receiving and processing resource allocation information from the BS, according to one embodiment. 
         FIG. 4B  illustrates a flowchart for a method of receiving and processing resource allocation information from the BS, according to another embodiment. 
         FIG. 5  illustrates a flowchart for an exemplary method of allocating resources to the MS, according to one embodiment. 
         FIG. 6  illustrates a schematic representation of frame structures associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier, according to one embodiment. 
         FIG. 7  illustrates a flowchart for an exemplary method of allocating resources to the MS, according to another embodiment. 
         FIG. 8  illustrates a schematic representation of frame structures associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier, according to another embodiment. 
         FIG. 9  illustrates a flowchart of an exemplary method of allocating resources to the MS, according to yet another embodiment. 
         FIG. 10  illustrates a schematic representation of frame structures associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier, according to yet another embodiment. 
         FIG. 11  illustrates a flowchart of an exemplary method of allocating resources to the MS, according to further another embodiment. 
         FIG. 12  illustrates a schematic representation of frame structures associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier, according to further another embodiment. 
         FIG. 13  illustrates a flowchart for an exemplary method of allocating resources to the MS, according to yet a further embodiment. 
         FIG. 14  illustrates a schematic representation of frame structures associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier, according to yet a further embodiment. 
         FIG. 15  illustrates a flowchart of an exemplary method of allocating resources to the MS, according to still another embodiment. 
         FIG. 16  illustrates a schematic representation of frame structures associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier, according to still another embodiment. 
         FIG. 17  illustrates a flowchart for an exemplary method of allocating resources to the MS, according to yet another embodiment. 
         FIG. 18  illustrates a schematic representation of frame structures associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier, according to yet another embodiment. 
         FIG. 19  illustrates a schematic representation of frame structures associated with a primary DL carrier, a secondary DL carrier, and a secondary carrier, according to another embodiment. 
         FIG. 20  illustrates a flowchart for an exemplary method of allocating resources to the MS, according to alternate embodiment. 
         FIG. 21  illustrates a schematic representation of frame structures associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier with multiple allocation intervals per subframe, according to one embodiment. 
         FIG. 22  illustrates a schematic representation of exemplary frame structures associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier with two allocation intervals per subframe, according to one embodiment. 
         FIG. 23  illustrates a schematic representation of exemplary frame structures associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier with two allocation intervals per subframe, according to another embodiment. 
         FIG. 24  illustrates a schematic representation of exemplary frame structures associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier with two allocation intervals per subframe, according to yet another embodiment. 
         FIG. 25  illustrates a schematic representation of exemplary frame structures associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier with three allocation intervals per subframe, according to one embodiment. 
         FIG. 26  illustrates a schematic representation of frame structures associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier with multiple allocation intervals per subframe, according to another embodiment. 
         FIG. 27  illustrates a schematic representation of frame structures associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier with multiple allocation intervals per subframe, according to yet another embodiment. 
         FIG. 28  illustrates a schematic representation of frame structures associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier with multiple allocation intervals per subframe, according to further another embodiment. 
         FIG. 29  illustrates a schematic representation of indication location of a Super Mobile Broadband (SMB) Physical Downlink Control Channel (S-PDCCH) region to the MS, according to one embodiment. 
         FIGS. 30A-C  illustrate schematic representations of indication of location of an S-PDCCH region to the MS, according to another embodiment. 
         FIG. 31  illustrates a schematic representation of frame structures in a Time Division Duplex (TDD) mode, according to one embodiment. 
         FIG. 32  illustrates a schematic representation of frame structures in the TDD mode, according to another embodiment. 
         FIG. 33  illustrates a schematic representation of frame structures in the TDD mode, according to yet another embodiment. 
         FIG. 34  illustrates a block diagram of an exemplary base station, such as those shown in  FIG. 2A , showing various components for implementing embodiments of the present subject matter. 
         FIG. 35  illustrates a block diagram of an exemplary mobile station, such as those shown in  FIG. 2A , showing various components for implementing embodiments of the present subject matter. 
     
    
    
     The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way. 
     DETAILED DESCRIPTION 
       FIGS. 1 through 35 , discussed below, and the various embodiments used to describe the principles of the present disclosure in this patent document are by way of illustration only and should not be construed in any way to limit the scope of the disclosure. Those skilled in the art will understand that the principles of the present disclosure may be implemented in any suitably arranged system or device. The present disclosure provides a method and system for signaling resource allocation information in an asymmetric multicarrier communication network. In the following detailed description of the embodiments of the disclosure, reference is made to the accompanying drawings that form a part hereof, and in which are shown by way of illustration specific embodiments in which the disclosure may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the disclosure, and it is to be understood that other embodiments may be utilized and that changes may be made without departing from the scope of the present disclosure. The following detailed description is, therefore, not to be taken in a limiting sense, and the scope of the present disclosure is defined only by the appended claims. 
     In an asymmetric multicarrier communication network, a mobile station (MS) communicates with a base station using asymmetric carriers consisting of at least one low frequency carrier in a cellular band and at least one high frequency carrier in a millimeter Wave band. The primary carrier, i.e., carrier operating on low frequencies, is used to transmit control information including resource allocation information for a secondary carrier, i.e., carrier operating on high frequencies. The primary carrier and the secondary carrier may be transmitted by same base station (BS) or different BS.  FIG. 2A  illustrates a schematic diagram  200  of an asymmetric multicarrier communication network where a primary carrier and a secondary carrier are transmitted by a same BS  202 .  FIG. 2B  illustrates a schematic diagram  250  of another asymmetric multicarrier communication network where a primary carrier and a secondary carrier are transmitted by different BSs  202 . In asymmetric multicarrier communication network, transmit time intervals (TTIs) and frame structures for the primary carrier are different than those of the secondary carrier. The present disclosure is applicable to any asymmetric multicarrier communication network, wherein at least one of transmit time interval (TTI) and frame structures on primary carrier are different than those of secondary carriers. 
     For the purpose explanation, low frequency carrier operation as defined in 3GPP LTE system is considered. However, the present disclosure is equally applicable to any other cellular broadband system. Further, control information is referred to in particular for resource allocation information; however the disclosure can be used for other types of control information wherever applicable. 
       FIG. 3  illustrates a flowchart  300  for a method of allocating resources to the MS  204 , according to one embodiment. At step  302 , resources for one or more transmit time intervals (TTIs) in at least one of DL allocation interval of a secondary DL carrier (e.g., Super Mobile Broadband (SMB) DL carrier) and UL allocation interval of a secondary UL carrier (e.g., SMB UL carrier) are allocated for the MS  204 , where the DL allocation interval spans one or more subframes of the secondary DL carrier and the UL allocation interval spans one or more subframes of the secondary UL carrier. At step  304 , information regarding the allocated resources is transmitted to the MS  204  in a PDCCH region of a subframe of a primary DL carrier (e.g., Long Term Evolution (LTE) carrier). In one embodiment, the information regarding the allocated resources is transmitted using SMB-Physical Downlink Control Channel (S-PDCCH) in a region designated for Physical Downlink Control Channel (PDCCH). In this embodiment, the information regarding the allocated resources is transmitted in first three or first four symbols of a first slot in the subframe of the primary DL carrier. The S-PDCCH may span one or more Orthogonal Frequency Division Multiplexing (OFDM) symbols in the PDCCH region. It can be noted that, the physical layer transmission of S-PDCCH follows PDCCH transmission attributes coding, modulation, etc.). 
       FIG. 4A  illustrates a process flowchart  400  for a method of receiving and processing resource allocation information from the BS  202 , according to one embodiment. At step  402 , transmissions are simultaneously received by the MS  204  on a subframe of a primary DL carrier and a subframe of a secondary DL carrier. At step  404 , the transmissions received on the subframe of secondary DL carrier is buffered at the MS  204  till Physical Control Format Indicator Channel (PCFICH) and PDCCH/S-PDCCH are received on the primary DL carrier and decoded by the MS  204 . 
     At step  406 , PCFICH is received in a first Orthogonal Frequency Division Multiplexing (OFDM) symbol of the subframe of the primary DL carrier. At step  408 , the PCFICH is decoded to determine presence of a PDCCH region in the subframe of the primary DL carrier. At step  410 , it is determined whether the PDCCH region is present in the subframe of the primary DL carrier. If the PDCCH region is not present in the subframe of the primary DL carrier, then at step  412 , reception of information on the subframe of the primary DL carrier and the subframe of the secondary DL carrier is terminated. Also, at step  414 , the information received on the secondary DL carrier and buffered at the MS  204  is deleted. 
     If the PDCCH region is present in the subframe of the primary DL carrier, then at step  416 , PDCCH(s) and/or S-PDCCH(s)) received in the PDCCH region are decoded. At step  418 , it is determined whether one or more S-PDCCHs are decoded in the PDCCH region. If the one or more S-PDCCHs are decoded in the PDCCH region, then at step  420 , the resource allocation information decoded from the one or more S-PDCCHs is processed. The resource allocation information indicates resources allocated for one or more transmit time intervals in at least one DL allocation interval in the secondary downlink carrier and UL allocation interval in the secondary UL carrier. In one embodiment, the resource allocation information enables to decode PHY burst(s) transmitted in one or more TTIs in the DL allocation interval. In another embodiment, the resource allocation information enables to transmit PHY burst(s) in one or more TTIs in the UL allocation interval. If the one or more S-PDCCH(s) are not decoded from the PDCCH region, then at step  422 , reception of information on the subframe of the primary DL carrier and the subframe of the secondary DL carrier are terminated. Also, at step  424 , the information received in the secondary DL carrier and buffered at the MS  204  is deleted. It is understood that, the method steps  402  to  424  are applicable for frame structures illustrated in  FIG. 6 . 
       FIG. 4B  illustrates a flowchart  450  for a method of receiving and processing resource allocation information from the BS, according to another embodiment. At step  452 , transmissions are received by the MS  204  on a subframe of a primary DL carrier. At step  454 , Physical Control Format Indicator Channel (PCFICH) is received in a first Orthogonal Frequency Division Multiplexing (OFDM) symbol of the subframe of the primary DL carrier. At step  456 , the PCFICH is decoded to determine presence of a PDCCH region in the subframe of the primary DL carrier. At step  458 , it is determined whether the PDCCH region is present in the subframe of the primary DL carrier. If the PDCCH region is not present in the subframe of the primary DL carrier, then at step  460 , reception of information on the subframe of the primary DL carrier is terminated. 
     If the PDCCH region is present in the subframe of the primary DL carrier, then at step  462 , PDCCH(s) and/or S-PDCCH(s)) received in the PDCCH region are decoded. At step  464 , it is determined whether one or more S-PDCCHs are decoded in the PDCCH region. If the one or more S-PDCCHs are decoded in the PDCCH region, then at step  466 , the resource allocation information decoded from the one or more S-PDCCHs is processed. The resource allocation information indicates resources allocated for one or more transmit time intervals in at least one DL allocation interval in the secondary downlink carrier and UL allocation interval in the secondary UL carrier. In one embodiment, the resource allocation information enables to decode PHY burst(s) transmitted in one or more TTIs in the DL allocation interval. In another embodiment, the resource allocation information enables to transmit PHY burst(s) in one or more TTIs in the UL allocation interval. If the one or more S-PDCCH(s) are not decoded from the PDCCH region, then at step  468 , reception of information on the subframe of the primary DL carrier is continued. It is understood that, the method steps  452  to  468  are applicable for frame structures illustrated in  FIGS. 8, 12, 14, 16, 18, and 20 . 
       FIG. 5  illustrates a flowchart  500  for an exemplary method of allocating resources to the MS  204 , according to one embodiment. At step  502 , resources for one or more transmit time intervals in at least one of DL allocation interval of a secondary DL carrier (e.g., SMB DL carrier) and UL allocation interval of a secondary UL carrier (e.g., SMB UL carrier) are allocated for the MS  204 , where the DL allocation interval spans a single subframe of the secondary DL carrier and the UL allocation interval spans multiple subframes of the secondary UL carrier. At step  504 , information regarding the allocated resources is transmitted to the MS  204  in a PDCCH region of a subframe of a primary DL carrier. It can be noted that, the subframes of primary DL carrier, the subframes of the secondary DL carrier and the subframes of the secondary UL carrier are time aligned with each other. Further, the DL allocation interval starts at the same time as the subframe of the primary DL carrier in which the resource allocation information for the DL allocation interval is transmitted. On the other hand, the UL allocation interval in the secondary UL carrier starts at a pre-defined offset during the time duration of the subframe of the primary DL carrier in which the resource allocation information for the UL allocation interval is transmitted. 
       FIG. 6  illustrates a schematic representation  600  of frame structures  602 A- 602 C associated with a primary Downlink (DL) carrier, a secondary DL carrier, and a secondary uplink (UL) carrier, according to one embodiment. In an exemplary implementation, the primary DL carrier may be a low frequency carrier in a long term evolution (LTE) band. In this exemplary implementation, the secondary DL carrier and the secondary UL carrier may be high frequency carrier in an mmWave band. One can envision that the primary DL carrier, the secondary DL carrier, and the secondary UL carrier may be associated with a frequency band associated with any radio access technology. 
     The frame structure  602 A includes a plurality of subframes  604 A-N of 1 millisecond duration. Each subframe is a transmit time interval for data packet. The starting of the each subframe  604  contains a control region  606  for transmitting information on resources allocated to the MS  204  followed by a data region for transmitting data packets in downlink direction. 
     The frame structure  602 B includes a plurality of subframes  608 A-N of 1 millisecond duration. Similarly, the frame structure  602 C includes a plurality of subframes  610 A-N. Each of the subframes  608 A-N and  610 A-N of the secondary DL carrier and the secondary UL carrier is divided into plurality of Transmit Time Intervals (TTIs)  609  of 0.1 millisecond duration. It can be noted that, the TTIs of each subframe of the secondary DL carrier and the secondary UL carrier are smaller time duration than a TTI in the primary DL carrier. The subframes  608 A-N and the subframes  610 A-N of the secondary DL carrier and the secondary UL carrier are time aligned with the subframes of the primary DL carrier. 
     According to the present disclosure, the base station  202  transmits information on allocated resources in the PDCCH region  606  of each subframe  604  of the primary DL carrier. The resource allocation information indicates resources allocated to the MS  204  for one or more transmit time intervals (TTIs) in a DL allocation interval  612  of the secondary DL carrier and an UL allocation interval  614  in the secondary UL carrier. The duration of the DL allocation interval  612  and the UL allocation interval  614  is equal to one subframe duration. Alternatively, the duration of the DL allocation interval  612  and the UL allocation interval  614  can be more than one subframe duration. As shown in  FIG. 6 , the DL allocation interval  612  spans a single subframe of the secondary DL carrier and the UL allocation interval  614  spans multiple subframes of the secondary UL carrier. For example, the DL allocation interval  612  spans the subframe  608 A while the UL allocation interval  614  spans the subframes  610 A and  610 B. That is, the DL allocation interval  612  starts at the same time as the subframe  604  of the primary DL carrier  604  in which the allocated resources for said DL allocation interval  612  are transmitted. The UL allocation interval  614  starts at a predefined offset  616  during time duration of the subframe  604  of the primary DL carrier in which the resource information for said UL allocation interval  614  is transmitted. The predefined offset  616  is equal to at least one of time duration of the PDCCH region  606  in which the resource information is transmitted, time duration required for processing the resource information, time duration required to switch from primary carrier to secondary carrier, time duration required to synchronize with the secondary carrier, time duration required to prepare uplink packet based on received resource allocation information, and time duration required for uplink timing advance. In some embodiments, maximum timing advance supported by the system  200  may be considered to calculate the predefined offset  616 . The pre-defined offset  616  may also include the time required to do beamforming. In beam-formed system, prior to transmission, appropriate beamforming needs to be performed in order to identify best transmit beam direction. 
       FIG. 7  illustrates a flowchart  700  for an exemplary method of allocating resources to the MS  204 , according to another embodiment. At step  702 , resources for one or more transmit time intervals in at least one of DL allocation interval of a secondary DL carrier (e.g., SMB DL carrier) and UL allocation interval of a secondary UL carrier (e.g., SMB UL carrier) are allocated for the MS  204 , where the DL allocation interval and the UL allocation interval spans multiple subframes of the secondary DL carrier and the secondary UL carrier, respectively. 
     At step  704 , information regarding the allocated resources is transmitted to the MS  204  in a PDCCH region of a subframe of a primary DL carrier. It can be noted that, the subframes of primary DL carrier, the subframes of the secondary DL carrier and the subframes of the secondary UL carrier are time aligned with each other. Further, the DL allocation interval starts at a first pre-defined offset during the time duration of the subframe of the primary DL carrier in which the resource allocation information for the DL allocation interval is transmitted. Similarly, the UL allocation interval in the secondary UL carrier starts at a second pre-defined offset during the time duration of the subframe of the primary DL carrier in which the resource allocation information for the UL allocation interval is transmitted. 
       FIG. 8  illustrates a schematic representation  800  of frame structures  802 A- 802 C associated with a primary Downlink (DL) carrier, a secondary DL carrier, and a secondary uplink (UL) carrier, according to another embodiment. It can be seen that the schematic representation  800  of  FIG. 8  is a similar to the schematic representation  600  of  FIG. 6 , except the DL allocation interval  812  spans multiple subframes of the secondary DL carrier. For example, the DL allocation interval  812  spans the subframes  808 A and  808 B and the UL allocation interval  814  spans the subframes  810 A and  810 B. That is, the DL allocation interval  812  starts at a first predefined offset  816  during time duration of the subframe  804  of the primary DL carrier in which the allocated resources for said DL allocation interval  812  are transmitted. The first predefined offset  816  is equal to at least one of time duration of the PDCCH region  806  in which resource allocation information is transmitted, time duration required for processing the resource allocation information, time duration required to switch from primary carrier to secondary carrier, and time duration require to synchronize with the secondary carrier. The first predefined offset  816  may also include time duration required to perform beamforming. In beam-formed system, prior to reception, appropriate beamforming needs to be performed in order to identify best transmit beam direction. 
     The UL allocation interval  814  starts at a second predefined offset  818  during time duration of the subframe  804  of the primary DL carrier in which the resource information for said UL allocation interval  814  is transmitted. The second predefined offset  818  is equal to at least one of time duration of the PDCCH region  806  in which the resource information is transmitted, time duration required for processing the resource information, time duration required to switch from primary carrier to secondary carrier, time duration required to synchronize with the secondary carrier, time duration required to prepare uplink packet based on received resource allocation information, and time duration required for uplink timing advance. In some embodiments, maximum timing advance supported by the system  200  may be considered to calculate the second predefined offset  818 . The second predefined offset  818  may also include time duration required to perform beamforming. In beam-formed system, prior to transmission, appropriate beamforming needs to be performed in order to identify best transmit beam direction. 
       FIG. 9  illustrates a flowchart  900  for an exemplary method of allocating resources to the MS  204 , according to yet another embodiment. At step  902 , resources for one or more transmit time intervals in at least one of DL allocation interval of a secondary DL carrier (e.g., SAM DL carrier) and UL allocation interval of a secondary UL carrier (e.g., SMB UL carrier) are allocated for the MS  204 , where the DL allocation interval and the UL allocation interval spans one subframe of the secondary DL carrier and the secondary UL carrier, respectively. 
     At step  904 , information regarding the allocated resources is transmitted to the MS  204  in a PDCCH region of a subframe of a primary DL carrier. It can be noted that, the subframes of the secondary DL carrier is time aligned with the subframes of the primary DL carrier whereas the subframes of the secondary UL carrier are offset by a pre-defined time duration with corresponding subframes of the primary DL carrier. Further, the DL allocation interval starts at the same time as the subframe of the primary DL carrier in which the resource allocation information for the DL allocation interval is transmitted. Similarly, the UL allocation interval in the secondary UL carrier starts at the same time as the subframe of the secondary UL carrier which starts at the pre-defined offset from the subframe of the primary DL carrier in which the resource allocation information for the UL allocation interval is transmitted. 
       FIG. 10  illustrates a schematic representation  1000  of frame structures  1002 A- 1002 C associated with a primary Downlink (DL) carrier, a secondary DL carrier, and a secondary uplink (UL) carrier, according to yet another embodiment. It can be seen from the schematic representation  1000  that the subframes  1008 A-N of the secondary downlink carrier are time aligned with corresponding subframes of the primary downlink carrier. It can also be seen that the subframes  1010 A-N of the secondary UL carrier are offset by pre-defined time duration  1016  with respect to the corresponding subframes  1004 A-N of the primary DL carrier. The pre-defined offset  1016  may be equal to at least one of time duration of the PDCCH region  1006  in which resource allocation information is transmitted, time duration required for processing the resource allocation information, time duration required to switch from primary carrier to secondary carrier, time duration required to synchronize with the secondary carrier, time duration required to prepare uplink packet based on the resource allocation information, time duration required for uplink timing advance, and time duration required for beamforming. 
     As depicted, the DL allocation interval  1012  starts at the same time as the subframe  1008  of the secondary DL carrier. Also, the UL allocation interval  1014  starts at the same time as the subframe  1010  of the secondary UL carrier. It can be noted that duration of the DL allocation interval  1012  and the UL allocation interval  1014  is equal to one subframe duration. Alternatively, the duration of the DL allocation interval  1012  and the UL allocation interval  1014  can be more than one subframe duration. 
       FIG. 11  illustrates a flowchart  1100  for an exemplary method of allocating resources to the MS  204 , according to further another embodiment. At step  1102 , resources for one or more transmit time intervals in at least one of DL allocation interval of a secondary DL carrier (e.g., SMB DL carrier) and UL allocation interval of a secondary UL carrier (e.g., SMB UL carrier) are allocated for the MS  204 , where the DL allocation interval spans multiple subframes of the secondary DL carrier and the UL allocation interval spans a single subframe of the secondary UL carrier. 
     At step  1104 , information regarding the allocated resources is transmitted to the MS  204  in a PDCCH region of a subframe of a primary DL carrier. It can be noted that, the subframes of the secondary DL carrier is time aligned with the subframes of the primary DL carrier whereas the subframes of the secondary UL carrier are offset by a first pre-defined time duration with corresponding subframes of the primary DL carrier. Further, the DL allocation interval starts at a second pre-defined offset during the time duration of the corresponding subframe of the primary DL carrier in which the resource allocation information for the DL allocation interval is transmitted. On the other hand, the UL allocation interval in the secondary UL carrier starts at the same time as the subframe of the secondary UL carrier which starts at the first pre-defined offset from the subframe of the primary DL carrier in which the resource allocation information for the UL allocation interval is transmitted. 
       FIG. 12  illustrates a schematic representation  1200  of frame structures  1202 A- 1202 C associated with a primary Downlink (DL) carrier, a secondary DL carrier, and a secondary uplink (UL) carrier, according to further another embodiment. It can be seen that the schematic representation  1200  is similar to the schematic representation  1000  of  FIG. 10  except the DL allocation interval  1212  spans multiple subframes of the secondary DL carrier. For example, the DL allocation interval  1212  spans the subframes  1208 A and  1208 B of the secondary DL carrier. That is, the DL allocation interval  1212  starts at a predefined offset  1216  during time duration of the subframe  1204  of the primary DL carrier in which the resource allocation information for said DL allocation interval  1212  is transmitted. The predefined offset  1218  is equal to at least one of time duration of the PDCCH region  1206  in which resource allocation information is transmitted, time duration required for processing the resource allocation information, time duration required to switch from primary carrier to secondary carrier, time duration require to synchronize with the secondary carrier, and time duration required for beamforming. 
       FIG. 13  illustrates a flowchart  1300  for an exemplary method of allocating resources to the MS  204 , according to yet a further embodiment. At step  1302 , resources for one or more transmit time intervals in at least one of DL allocation interval of a secondary DL carrier (e.g., SMB DL carrier) and UL allocation interval of a secondary UL carrier (e.g., SMB UL carrier) are allocated for the MS  204 , where the DL allocation interval and the UL allocation interval span a single subframe of the secondary DL carrier and the secondary UL carrier, respectively. 
     At step  1304 , information regarding the allocated resources is transmitted to the MS  204  in a PDCCH region of a subframe of a primary DL carrier. It can be noted that, the subframes of the secondary DL carrier and the subframes of the secondary UL carrier are time aligned with each other and are offset by a pre-defined time duration with corresponding subframes of the primary DL carrier. Further, the DL allocation interval in the secondary DL carrier starts at the same time as the subframe of the secondary DL carrier which starts at the pre-defined offset from the corresponding subframe of the primary DL carrier in which the resource allocation information for the DL allocation interval is transmitted. Similarly, the UL allocation interval in the secondary UL carrier starts at the same time as the subframe of the secondary UL carrier which starts at the pre-defined offset from the subframe of the primary DL carrier in which the resource allocation information for the UL allocation interval is transmitted. 
       FIG. 14  illustrates a schematic representation  1400  for frame structures  1402 A- 1402 C associated with a primary Downlink (DL) carrier, a secondary DL carrier, and a secondary uplink (UL) carrier, according to yet a further embodiment. In  FIG. 14 , subframes  1408 A-N of the secondary DL carrier and subframes  1410 A-N of the secondary UL carrier are time aligned with each other and offset by pre-defined time duration  1416  with corresponding subframes  1404 A-N of the primary DL carrier. The pre-defined offset  1416  is equal to at least one of time duration of the PDCCH region  1406  in which resource allocation information is transmitted, time duration required for processing the resource allocation information, time duration required to switch from primary carrier to secondary carrier, time duration required to synchronize with the secondary carrier, time duration required for preparing UL packet and time required to perform beamforming. Alternatively, the pre-defined offset  1416  may be equal to time duration of the PDCCH region  1406  in which resource allocation information is transmitted plus time duration required for processing the resource allocation information plus maximum of time duration required to switch from primary carrier to secondary carrier, time duration required to synchronize with the secondary carrier, time duration required for preparing UL packet, time required to perform beamforming and time duration required for uplink timing advance. In some embodiments, maximum timing advance supported by the asymmetric multicarrier system may be considered to calculate the pre-defined offset. 
     Further, it can be seen that, DL allocation interval  1412  in the secondary DL carrier and is time aligned with subframes  1408 A-N of the secondary DL carrier. Similarly, UL allocation interval  1414  in the secondary DL carrier is time aligned with the subframes  1410 A-N of the secondary UL carrier. It can also be noted that, duration of the DL allocation interval  1412  and the UL allocation interval  1414  is equal to single subframe duration. Alternatively, the duration of the DL allocation interval  1012  and the UL allocation interval  1014  may be greater than one subframe duration. 
       FIG. 15  illustrates a flowchart  1500  for an exemplary method of allocating resources to the MS  204 , according to still another embodiment. At step  1502 , resources for one or more transmit time intervals in at least one of DL allocation interval of a secondary DL carrier (e.g., SMB DL carrier) and UL allocation interval of a secondary UL carrier (e.g., SMB UL carrier) are allocated for the MS  204 , where the DL allocation interval spans a single subframe of the secondary DL carrier and the UL allocation interval spans multiple subframes of the secondary UL carrier. 
     At step  1504 , information regarding the allocated resources is transmitted to the MS  204  in a PDCCH region of a subframe of a primary DL carrier. It can be noted that, the subframes of the secondary DL carrier and the subframes of the secondary UL carrier are time aligned with each other and are offset by a first pre-defined time duration with corresponding subframes of the primary DL carrier. Further, the DL allocation interval in the secondary DL carrier starts at the same time as the subframe of the secondary DL carrier which starts at the pre-defined offset from the corresponding subframe of the primary DL carrier in which the resource allocation information for the DL allocation interval is transmitted. On the other hand, the UL allocation interval in the secondary UL carrier starts at a second predefined offset from the subframe of the secondary UL carrier which starts at the first pre-defined offset from the subframe of the primary DL carrier in which the resource allocation information for the UL allocation interval is transmitted. 
       FIG. 16  illustrates a schematic representation  1600  for frame structures  1602 A- 1602 C associated with a primary Downlink (DL) carrier, a secondary DL carrier, and a secondary uplink (UL) carrier, according to still another embodiment. It can be seen that the schematic representation  1600  is similar to the schematic representation  1400  of  FIG. 14 , except that UL allocation interval  1614  starts at a predefined offset  1618  from the corresponding subframes  1610 A-N of the secondary UL carrier. In one embodiment, the predefined offset  1618  is equal to time duration required to build an uplink packet. In another embodiment, the predefined offset  1618  is equal to time duration required to build an uplink packet minus time duration required to switch and synchronize to secondary carrier and time duration required to perform beamforming. The predefined offset is calculated as described above when the predefined offset  1616  is computed using time duration required to switch and synchronize to secondary carrier and time duration required to perform beamforming. Also, the predefined offset  1616  may include time duration required for uplink timing advance. In one exemplary implementation, maximum timing advance supported by the asymmetric multicarrier system may be considered to compute the pre-defined offset. As depicted in  FIG. 16 , the UL allocation interval  1614  spans multiple subframes of the secondary UL carrier. It can also be seen that subframes  1608 A-N of the secondary DL carrier and subframes  1610 A-N of the secondary UL carrier are time aligned with each other and offset by pre-defined time duration  1616  with corresponding subframes  1604 A-N of the primary DL carrier. The pre-defined time duration  1616  is equal to at least one of time duration of the PDCCH region  1606  in which resource allocation information is transmitted, time duration required for processing the resource allocation information, time duration required to switch from primary carrier to secondary carrier time duration required to synchronize with the secondary carrier, and time required to perform beamforming. 
       FIG. 17  illustrates a process flowchart  1700  for an exemplary method of allocating resources to the MS  204 , according to yet another embodiment. At step  1702 , resources for one or more transmit time intervals in at least one of DL allocation interval of a secondary DL carrier (e.g., SMB DL carrier) and UL allocation interval of a secondary UL carrier (e.g., SMB UL carrier) allocated for the MS  204 , where the DL allocation interval and the UL allocation interval span single subframe of the secondary DL carrier and the secondary UL carrier, respectively. 
     At step  1704 , information regarding the allocated resources is transmitted to the MS  204  in a PDCCH region of a subframe of a primary DL carrier. It can be noted that, the subframes of the secondary DL carrier is offset by a first pre-defined time duration with corresponding subframes of the primary DL carrier. Similarly, the subframes of the secondary UL carrier are offset by a second pre-defined time duration with corresponding subframes of the primary DL carrier. Further, the DL allocation interval in the secondary DL carrier starts at the same time as the subframe of the secondary DL carrier which starts at the first pre-defined offset from the corresponding subframe of the primary DL carrier in which the resource allocation information for the DL allocation interval is transmitted. Similarly, the UL allocation interval in the secondary UL carrier starts at the same time as the subframe of the secondary UL carrier which starts at the second pre-defined offset from the subframe of the primary DL carrier in which the resource allocation information for the UL allocation interval is transmitted. 
       FIG. 18  illustrates a schematic representation  1800  of frame structures  1802 A- 1802 C associated with a primary Downlink (DL) carrier, a secondary DL carrier, and a secondary uplink (UL) carrier, according to yet another embodiment. It can be seen that the schematic representation  1800  is similar to the schematic representation  1400  of  FIG. 14 , except that subframes  1810 A-N of the secondary UL carrier are offset by predefined time duration  1818  with the corresponding subframes  1804 A-N of the primary DL carrier. In one embodiment, the predefined offset  1818  is equal to time duration required to build an uplink packet. In another embodiment, the predefined offset  1818  is equal to time duration required to build an uplink packet minus time duration required to switch and synchronize to secondary carrier and time duration required to perform beamforming. The predefined offset  1818  is calculated as described above when the predefined offset  1816  is computed using time duration required to switch and synchronize to secondary carrier and time duration required to perform beamforming. Also, the predefined offset  1816  may include time duration required for uplink timing advance. In one exemplary implementation, maximum timing advance supported by the asymmetric multicarrier system may be considered to compute the pre-defined offset. As depicted in  FIG. 18 , the UL allocation interval  1814  spans multiple subframes of the secondary UL carrier. It can be seen that subframes  1808 A-N of the secondary DL carrier and subframes  1810 A-N of the secondary UL carrier are time aligned with each other and offset by pre-defined time duration  1816  with corresponding subframes  1804 A-N of the primary DL carrier. The pre-defined time duration  1816  is equal to at least one of time duration of the PDCCH region  1806  in which resource allocation information is transmitted, time duration required for processing the resource allocation information, time duration required to switch from primary carrier to secondary carrier time duration required to synchronize with the secondary carrier, and time required to perform beamforming. As depicted, UL allocation interval  1814  starts at the same time as the subframe of the secondary UL carrier. 
       FIG. 19  illustrates a schematic representation  1900  of frame structures  1902 A- 1902 C associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier, according to another embodiment. It can be seen that the schematic representation  1900  is similar to the schematic representation  600  of  FIG. 6 , except that a DL allocation interval  1912  of the secondary DL carrier and an UL allocation interval  1914  of the secondary UL carrier do not comprise TTIs of a subframe which are overlapping the PDCCH region  1906  of a subframe (e.g., subframe  1904 B) of the primary DL carrier. That is, TTIs in a subframe of the secondary DL carrier and the secondary UL carrier that overlap with time duration of the PDCCH region are unutilized especially when one radio frequency (RF) unit needs to be in ON state at a single instance. It can be noted that, the above condition is also applicable to the embodiments illustrated in  FIGS. 5 to 18 . 
       FIG. 20  illustrates a flowchart  2000  for an exemplary method of allocating resources to the MS  204 , according to alternate embodiment. At step  2002 , resources for one or more transmit time intervals (TTIs) in a group of DL allocation intervals of a secondary DL carrier and a group of UL allocation intervals of a secondary UL carrier are allocated to the MS  204 . The group of DL allocation intervals is contiguous. Also, the group of UL allocation intervals is contiguous. 
     At step  2004 , an S-PDCCH region from a plurality of S-PDCCH regions in a subframe of a primary DL carrier is determined for transmitting information on the allocated resources. It can be noted that, each of the control regions is configured for carrying resource allocation information associated with one of the group of DL allocation intervals and one of the group of UL allocation intervals. At step  2006 , the resource allocation information is transmitted in the determined control region of the subframe in the primary DL carrier. 
       FIG. 21  illustrates a schematic representation  2100  for frame structures  2102 A- 2102 C associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier with multiple allocation intervals per subframe, according to one embodiment. The frame structure  2102 A includes a plurality of subframes  2104 A-N of 1 millisecond duration. Each of the subframes  2104 A-N of the primary DL carrier is divided into two slots  2105 A and  2105 B. The first slot  2105 A of the subframes  2104 A-N contains a PDDCH region  2106  and a data region  2109  whereas the second slot  2105 B includes the data region  2109 . Multiple S-PDCCH regions  2107 A-N are defined in each subframe of the primary DL carrier. The S-PDCCH region  2107 A is located in the PDCCH region  2106  and the S-PDCCH regions  2107 B-N are located in the data region  2109  in the first slot  2105 A and the second slot  2105 B. The S-PDCCH regions  2107 A-N may be of same or different sizes. 
     The frame structure  2102 B includes a plurality of subframes  2108 A-N of 1 millisecond duration, each subframe  2108  of the secondary DL carrier is divided into multiple DL allocation intervals  2112 A-N. Similarly, the frame structure  2102 C includes a plurality of subframes  2110 A-N, each subframe  2110  of the secondary UL carrier is divided into multiple UL allocation intervals  2114 A-N. It can be noted that, number of S-PDCCH regions  2107 A-N is equal to number of allocation intervals in one subframe duration (e.g., 1 ms). Each S-PDCCH region carries S-PDCCH for one DL allocation interval and one UL allocation interval. The mapping of S-PDCCH regions  2107 A-N to DL allocation intervals  2112 A-N and UL allocation interval  2114 A-N are pre-defined by the BS  202 . Alternatively, the mapping of S-PDCCH regions  2107 A-N to DL allocation intervals  2112 A-N and UL allocation interval  2114 A-N is fixed. 
     In an embodiment illustrated in  FIG. 21  the subframes  2108 A-N of the secondary DL carrier are time aligned with the subframes  2104 A-N of the primary DL carrier whereas the subframes  2110 A-N of the secondary UL carrier are offset to the end of the first S-PDCCH region  2107 B in the data region  2109  in the subframes  2104 A-N by a time duration required for processing the resource allocation information and time duration required for preparing UL packet. In this embodiment, the DL allocation intervals  2112 A-N and the UL allocation intervals  2114 A-N are time aligned to boundary of the respective subframes  2108 A-N and  2110 A-N. In this case, there is a need to buffer data received on the DL allocation intervals  2112 A-N. In another embodiment, the subframes  2110 A-N of the secondary DL carrier are offset to the end of the first S-PDCCH region  2107 B in the data region  2109  in the subframes  2104 A-N by a time duration required for processing the resource allocation information by at least an amount equal to time duration required for processing the resource allocation information. In yet another embodiment, DL allocation intervals  2112 A-N of the secondary DL carrier and UL allocation intervals  2114 A-N are offset from end of the first S-PDCCH region  2107 B in the data region  2109  of the subframes  2104 A-N by an amount equal to a time duration required to process resource allocation information while subframes  2108 A-N of the secondary DL carrier and subframes  2110 A-N of the secondary UL carrier are time aligned with subframes  2104 A-N of the primary DL carrier. 
     As illustrated in  FIG. 21 , the BS  202  transmits resource allocation information for the DL allocation interval  2112 A and UL allocation interval  2114 A in the S-PDCCH region  2107 A, DL allocation interval  2112 B and UL allocation interval  2114 B in the S-PDCCH region  2107 B, DL allocation interval  2112 C and UL allocation interval  2114 C in the S-PDCCH region  2107 C, and DL allocation interval  2112 D and UL allocation interval  2114 D in the S-PDCCH region  2107 D. 
       FIG. 22  illustrates a schematic representation  2200  of exemplary frame structures  2202 A- 2202 C associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier with two allocation intervals per subframe, according to one embodiment. The frame structure  2202 A includes a plurality of subframes  2204 A-N of 1 millisecond duration. Each of the subframes  2204 A-N of the primary DL carrier is divided into two slots  2205 A and  2205 B. The first slot  2205 A of the each subframe  2204  contains a PDDCH region  2206  and a data region  2209  whereas the second slot  2205 B includes the data region  2209 . The first S-PDCCH region  2207 A is located in the PDCCH region  2206  and the second S-PDCCH region  2207 B spans all symbols of the data region  2209  in the first slot  2205 A and the second slot  2205 B. The second S-PDCCH region  2207 B is composed of same sub carriers in frequency domain for all symbols in the data region  2209 . 
     The frame structure  2202 B includes a plurality of subframes  2208 A-N of 1 millisecond duration, each subframe  2208  of the secondary DL carrier is divided into two allocation intervals  2212 A and  2212 B. Similarly, the frame structure  2202 C includes a plurality of subframes  2210 A-N, each subframe  2210  of the secondary UL carrier is divided into two allocation intervals  2214 A and  2214 B. In an embodiment illustrated in  FIG. 22 , the subframes  2208 A-N of the secondary DL carrier are time aligned with the subframes  2204 A-N of the primary DL carrier whereas the subframes  2210 A-N of the secondary UL carrier are offset to the end of the corresponding subframes  2204 A-N of the primary DL carrier by a time duration required for processing the resource allocation information and time duration required for preparing UL packet. In another embodiment, the subframes  2210 A-N of the secondary DL carrier are offset with respect to the corresponding subframes  2204 A-N of the primary DL carrier such that the second allocation interval  2212 B is offset to the end of the corresponding subframes  2204 A-N of the primary DL carrier by at least an amount equal to time duration required for processing the resource allocation information. 
     According to the present disclosure, the base station  202  transmits information on allocated resources for the first allocation interval  2212 A in the secondary DL carrier and the first allocation interval  2214 A in the secondary UL carrier in the first S-PDCCH region  2207 A. Similarly, the base station  202  transmits information on the allocated resources for the second allocation interval  2212 B in the secondary DL carrier and the second allocation interval  2214 B in the secondary UL carrier in the second S-PDCCH region  2207 B. 
       FIG. 23  illustrates a schematic representation  2300  of exemplary frame structures  2302 A- 2302 C associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier with two allocation intervals per subframe, according to another embodiment. It can be seen that, the schematic representation  2300  is similar to the schematic representation  2200  of  FIG. 22 , except that the first S-PDCCH region  2307 A is located in the PDCCH region  2306  in the first slot  2305 A and the second S-PDCCH region  2307 B in the data region  2309  in the second slot  2305 B of the subframes  2304 A-N in the primary DL carrier. That is, the second S-PDCCH region  2307 B spans all symbols of the second slot  2305 B. 
     Also, the subframes  2308 A-N of the secondary DL carrier are time aligned with the subframes  2304 A-N of the primary DL carrier whereas the subframes  2310 A-N of the secondary UL carrier are offset to the end of the first slot  2305 A of the corresponding subframes  2304 A-N of the primary DL carrier by a time duration required for processing the resource allocation information and time duration required for preparing UL packet. Further, the subframes  2310 A-N of the secondary DL carrier are offset with respect from the first slot  2305 A of the corresponding subframes  2304 A-N of the primary DL carrier by at least an amount equal to time duration required for processing the resource allocation information. 
       FIG. 24  illustrates a schematic representation  2400  of exemplary frame structures  2402 A- 2402 C associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier with two allocation intervals per subframe, according to yet another embodiment. It can be seen that, the schematic representation  2400  is similar to the schematic representation  2300  of  FIG. 23 , except that the first S-PDCCH region  2407 A is located in the data region  2409  in the first slot  2405 A instead of the PDCCH region  2406 . That is, the first S-PDCCH region  2407 A spans all symbols of the data region  2409  in the first slot  2405 A and the second S-PDCCH region  2407 B spans all symbols of the data region  2409  in the second slot  2405 B. The first S-PDCCH region  2407 A is composed of same sub carriers in frequency domain for all symbols in the data region  2409  of the first slot  2405 A, Similarly, the second S-PDCCH region  2407 B is composed of the same sub carriers as the first S-PDCCH region  2407 A in frequency domain for all symbols. Alternatively, the second S-PDCCH region  2407 B is composed of same sub carriers in frequency domain for all symbols in the data region  2409  in the second slot  2405 B. 
       FIG. 25  illustrates a schematic representation  2500  of exemplary frame structures  2502 A- 2502 C associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier with three allocation intervals per subframe, according to one embodiment. The frame structure  2502 A includes a plurality of subframes  2504 A-N of 1 millisecond duration. Each of the subframes  2504 A-N of the primary DL carrier is divided into two slots  2505 A and  2505 B. The first slot  2505 A of the each subframe  2504  contains PDDCH region  2506  and data region  2509  whereas the second slot  2505 B includes data region  2509 . The first S-PDCCH region  2507 A is located in the PDCCH region  2506  and second S-PDCCH region  2507 B is located in the data region  2509  in the first slot  2505 A. The third S-PDCCH region  2507 C is located in the data region  2509  of the second slot  2505 B. The second S-PDCCH region  2507 B spans all symbols in the data region  2509  of the first slot  2505 A. The second S-PDCCH region  2507 B is composed on same sub carriers in frequency domain for all symbols in the data region  2509  of the first slot  2505 A. The third S-PDCCH region  2507 C spans all symbols of the second slot  2505 B. The third S-PDCCH region  2507 C is composed of same sub carriers in frequency domain for all symbols. In one embodiment, subcarriers for the second S-PDCCH region  2507 B and the third S-PDCCH region  2507 C are same. In another embodiment, subcarriers for the second S-PDCCH region  2507 B and the third S-PDCCH region  2507 C are different. 
     The frame structure  2502 B includes a plurality of subframes  2508 A-N of 1 millisecond duration, each subframe  2508  is divided into three allocation intervals  2512 A,  2512 B and  2512 C. Similarly, the frame structure  2502 C includes a plurality of subframes  2510 A-N, each subframe  2210  is divided into three allocation intervals  2514 A,  2514 B and  2514 C. 
     According to the present disclosure, the base station  202  transmits information on allocated resources for the first allocation interval  2512 A in the secondary DL carrier and the first allocation interval  2514 A in the secondary UL carrier in the first S-PDCCH region  2507 A. Similarly, the base station  202  transmits information on the allocated resources for the second allocation interval  2512 B in the secondary DL carrier and the second allocation interval  2514 B in the secondary UL carrier in the second S-PDCCH region  2507 B. Also, the base station  202  transmits information on the allocated resources for the third allocation interval  2512 C in the secondary DL carrier and the third allocation interval  2514 C in the secondary UL carrier in the third S-PDCCH region  2507 C. 
       FIG. 26  illustrates a schematic representation  2600  of frame structures  2602 A- 2602 C associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier with multiple allocation intervals per subframe, according to another embodiment. It can be seen that, the schematic representation  2600  is similar to the schematic representation  2100  of  FIG. 21 , except that multiple S-PDCCH regions  2607 A-N are located in data portion of subframe in the primary DL carrier. 
       FIG. 27  illustrates a schematic representation  2700  of frame structures  2702 A- 2702 C associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier with multiple allocation intervals per subframe, according to another embodiment. It can be seen that, the schematic representation  2700  is similar to the schematic representation  2600  of  FIG. 26 , except that subframes  2708 A-N of the secondary DL carrier is offset from end of a first S-PDCCH region  2707 A by an amount equal to a time duration required to process resource allocation information. 
       FIG. 28  illustrates a schematic representation  2800  of frame structures  2802 A- 2802 C associated with a primary DL carrier, a secondary DL carrier, and a secondary UL carrier with multiple allocation intervals per subframe, according to further another embodiment. It can be seen that, the schematic representation  2800  is similar to the schematic representation  2600  of  FIG. 26 , except that allocation intervals  2812 A-N of the secondary DL carrier and allocation intervals  2814 A-N are offset from end of a first S-PDCCH region  2807 A by an amount equal to a time duration required to process resource allocation information while subframes  2808 A-N of the secondary DL carrier and subframes  2810 A-N of the secondary UL carrier are time aligned with subframes  2804 A-N of the primary DL carrier. 
       FIG. 29  illustrates a schematic representation  2900  of an indication location of an S-PDCCH region to the MS  204 , according to one embodiment. The BS  202  indicates S-PDCCH region into a PDCCH region via PDCCH. The S-PDCCH region indicated by the BS  202  is logically divided into multiple S-PDCCH sub regions. The S-PDCCH region may be scattered in frequency domain composing of different subcarriers. The scattered regions are treated as a single whole region for division into multiple S-PDCCH sub regions. 
       FIGS. 30A-C  illustrate schematic representations of indication of location of an S-PDCCH region to the MS  204 , according to another embodiment. The BS  202  indicates location of multiple S-PDCCH regions in PDCCH region via a PDCCH. In one embodiment, the multiple S-PDCCH regions together span all portions of data region of subframe in the primary DL carrier. In another embodiment, the multiple S-PDCCH regions in total span multiple but not all symbols in the data region of the subframe in the primary DL carrier. In yet another embodiment, each S-PDCCH region spans a single symbol in the data portion of the subframe in the primary DL carrier. Each S-PDCCH region is located in a different symbol. It can be noted that, mapping of S-PDCCH region to respective allocation intervals is pre-defined and is known to both the MS  204  and the BS  202 . It is understood that, embodiments of the present disclosure as illustrated in  FIGS. 5 to 19  are also applicable to embodiments illustrated in  FIGS. 20 to 28 . 
     In accordance to the embodiments illustrated in  FIGS. 5 to 30A , parameters required for alignment of sub frames of a secondary DL carrier and secondary UL carrier includes time duration required to transmit resource allocation information, time duration required for processing the resource allocation information, time duration required to prepare UL packet, and time required for switching and synchronizing to secondary carrier. 
     When a subframe of the secondary DL carrier and/or the secondary UL carrier is offset with respect to subframe of primary DL carrier, the above parameters are defined to be constant for the asymmetric multicarrier communication network. That is, the values of the said parameters are same for all MSs in the asymmetric multicarrier communication network. In such a scenario, a cumulative value of the said parameters can be defined separately for the secondary DL carrier and the secondary UL carrier. The cumulative value may be either pre-specified or may be broadcasted in broadcast channel information. 
     When subframes of the secondary DL carrier and the secondary UL carrier are aligned with subframes of the primary DL carrier but DL allocation interval and UL allocation interval are offset to the corresponding sub frame boundaries, the value of the said parameters can be specifically defined each MS. In such a case, the values of the said parameters need to be indicated by each MS  204  to the BS  202 . In an exemplary implementation, value of each of these parameters is separately indicated by the MS to the BS. In another exemplary implementation, an indicator of cumulative values of the said parameters can be indicated by each MS  204  to the BS  202 . In some embodiments, the MS  204  may indicate the MS&#39;s category to the BS  202 , where the category is indicative of the cumulative values of the said parameters. For example, a high end MS which has higher processing capability has lower cumulative value of the said parameters while a low end MS which has lower processing capability has higher cumulative value of the said parameters. In such a case, the MS  204  indicates whether the MS is a high end or a low end MS. The MS  202  may indicate the category to the BS  202  via a capability negotiation message. Accordingly, the BS applies the corresponding cumulative value of the said parameters. 
       FIG. 31  illustrates a schematic representation  3100  of frame structures  3102 A and  3102 B in a Time Division Duplex (TDD) mode, according to one embodiment. The frame structure  3102 A includes a plurality of subframes  3104 A-N of 1 millisecond duration. Each of the subframes  3104 A-N of the primary DL carrier is divided into two slots  3105 A and  3105 B. The first slot  3105 A of the each subframe  3104  contains a PDDCH region  3106  and a data region  3109  whereas the second slot  3105 B includes data region  3109 . The S-PDCCH region  3107 A is located in the PDCCH region  3106  and the S-PDCCH region  3107 B is located in the data region  3109 . Alternatively, the S-PDCCH regions  3107 A-N are located in the data region  3109 . It can be noted that, the number of S-PDCCH regions is equal to the number of allocation Intervals in a sub frame of a secondary carrier. The mapping of S-PDCCH regions to allocation interval is pre-defined. 
     The frame structure  3102 B includes a plurality of subframes  3108 A-N of 1 millisecond duration. Each subframe  3108  of the secondary carrier is divided into five allocation intervals  3110 A-E. The allocation intervals  3110 A-E includes three DL allocation intervals  3110 A-C and two UL allocation intervals  3110 D and  3110 E. 
     As illustrated, the subframes  3108 A-N of the secondary carrier are time aligned with the subframes  3104 A-N of the primary carrier. Alternatively, the subframes  3108 A-N of the secondary carrier are offset by a pre-defined time duration with respect to the subframes  3104 A-N of the primary carrier. The pre-defined time duration is equal to time duration for receiving resource allocation information and/or time duration for processing the resource allocation information. 
       FIG. 32  illustrates a schematic representation  3200  of frame structures  3202 A and  3202 B in a Time Division Duplex (TDD) mode, according to another embodiment. It can been seen that, the schematic representation  3100  of  FIG. 31  is same as the schematic representation  3200  except that information of the S-PDCCH region  3207  in the data region  3209  is indicated in a PDCCH transmitted in the PDCCH region  3206 . The S-PDCCH region  3207  may be further divided into multiple S-PDCCH regions such that each S-PDCCH region corresponds to single allocation interval. The mobile station  204  may use a reserved Cell Radio Network Temporary Identifier (C-RNTI) for decoding the PDCCH carrying information of the S-PDCCH region  3207 . When there are multiple S-PDCCH regions in the data region  3209 , information on each S-PDCCH region is indicated by a different PDCCH. Alternatively, information of S-PDCCH region(s) in the data region  3209  is communicated in a broadcast information (e.g., primary broadcast channel (BCH)). Also, information of S-PDCCH region(s) in the data region  3209  may be communicated in a unicast manner in a signaling message during activation of the secondary carrier. It can be noted that, the BS  202  need not communicate the information on S-PDCCH region(s) if a pre-specified region in the data region  3209  is designated as S-PDCCH region(s). 
       FIG. 33  illustrates a schematic representation  3300  of frame structures  3302 A and  3302 B in a Time Division Duplex (TDD) mode, according to yet another embodiment. It can be noted that the schematic representation  3200  of  FIG. 32  is similar to the schematic representation  3300 , except location of PDCCH which carries information of S-PDCCH region(s). 
       FIG. 34  illustrates a block diagram of the base station  202  showing various components for implementing embodiments of the present subject matter. In  FIG. 34 , the base station  202  includes a processor  3402 , a memory  3404 , a read only memory (ROM)  3406 , a transceiver  3408 , and a bus  3410 . 
     The processor  3402 , as used herein, means any type of computational circuit, such as, but not limited to, a microprocessor, a microcontroller, a complex instruction set computing microprocessor, a reduced instruction set computing microprocessor, a very long instruction word microprocessor, an explicitly parallel instruction computing microprocessor, a graphics processor, a digital signal processor, or any other type of processing circuit. The processor  3402  may also include embedded controllers, such as generic or programmable logic devices or arrays, application specific integrated circuits, single-chip computers, smart cards, and the like. 
     The memory  3404  and the ROM  3406  may be volatile memory and non-volatile memory. The memory  3404  includes a resource allocation module  3412  for allocating resources for one or more transmit time intervals in at least one of downlink allocation interval in a secondary downlink carrier and uplink allocation interval in a secondary uplink carrier, according to one or more embodiments described above. A variety of computer-readable storage media may be stored in and accessed from the memory elements. Memory elements may include any suitable memory devices) for storing data and machine-readable instructions, such as read only memory, random access memory, erasable programmable read only memory, electrically erasable programmable read only memory, hard drive, removable media drive for handling compact disks, digital video disks, diskettes, magnetic tape cartridges, memory cards, and the like. 
     Embodiments of the present subject matter may be implemented in conjunction with modules, including functions, procedures, data structures, and application programs, for performing tasks, or defining abstract data types or low-level hardware contexts. The resource allocation module  3412  may be stored in the form of machine-readable instructions on any of the above-mentioned storage media and may be executable by the processor  3402 . For example, a computer program may include machine-readable instructions which when executed by the processor  3402 , may cause the processor  3402  to allocate resources for one or more transmit time intervals in at least one of downlink allocation interval in a secondary downlink carrier and uplink allocation interval in a secondary uplink carrier, according to the teachings and herein described embodiments of the present subject matter. In one embodiment, the program may be included on a compact disk-read only memory (CD-ROM) and loaded from the CD-ROM to a hard drive in the non-volatile memory. 
     The transceiver  3408  may be capable of transmitting resource allocation information in a subframe of a primary downlink carrier. The bus  3410  acts as interconnect between various components of the base station  202 . 
       FIG. 35  illustrates a block diagram of the mobile station  204  showing various components for implementing embodiments of the present subject matter. In  FIG. 35 , the mobile station  204  includes a processor  3502 , memory  3504 , a read only memory (ROM)  3506 , a transceiver  3508 , a bus  3510 , a display  3512 , an input device  3514 , and a cursor control  3516 . 
     The processor  3502 , as used herein, means any type of computational circuit, such as, but not limited to, a microprocessor, a microcontroller, a complex instruction set computing microprocessor, a reduced instruction set computing microprocessor, a very long instruction word microprocessor, an explicitly parallel instruction computing microprocessor, a graphics processor, a digital signal processor, or any other type of processing circuit. The processor  3502  may also include embedded controllers, such as generic or programmable logic devices or arrays, application specific integrated circuits, single-chip computers, smart cards, and the like. 
     The memory  3504  and the ROM  3506  may be volatile memory and non-volatile memory. The memory  3504  includes a resource allocation decoding module  3518  for decoding resource allocation information received from the base station  202  in the subframe of the primary downlink carrier, according to one or more embodiments described in  FIG. 4 . A variety of computer-readable storage media may be stored in and accessed from the memory elements. Memory elements may include any suitable memory device(s) for storing data and machine-readable instructions, such as read only memory, random access memory, erasable programmable read only memory, electrically erasable programmable read only memory, hard drive, removable media drive for handling compact disks, digital video disks, diskettes, magnetic tape cartridges, memory cards, and the like. 
     Embodiments of the present subject matter may be implemented in conjunction with modules, including functions, procedures, data structures, and application programs, for performing tasks, or defining abstract data types or low-level hardware contexts. The resource allocation decoding module  3518  may be stored in the form of machine-readable instructions on any of the above-mentioned storage media and may be executable by the processor  3502 . For example, a computer program may include machine-readable instructions, that when executed by the processor  3502 , cause the processor  3502  to decode resource allocation information received from the base station  202  in the subframe of the primary downlink carrier, according to the teachings and herein described embodiments of the present subject matter. In one embodiment, the computer program may be included on a compact disk-read only memory (CD-ROM) and loaded from the CD-ROM to a hard drive in the non-volatile memory. 
     The transceiver  3508  may be capable of receiving the resource allocation information in each subframe of the primary downlink carrier. The bus  3510  acts as interconnect between various components of the mobile station  204 . The components such as the display  3512 , the input device  3514 , and the cursor control  3516  are well known to the person skilled in the art and hence the explanation is thereof omitted. 
     The present embodiments have been described with reference to specific example embodiments; it will be evident that various modifications and changes may be made to these embodiments without departing from the broader spirit and scope of the various embodiments. Furthermore, the various devices, modules, and the like described herein may be enabled and operated using hardware circuitry, for example, complementary metal oxide semiconductor based logic circuitry, firmware, software and/or any combination of hardware, firmware, and/or software embodied in a machine readable medium. For example, the various electrical structure and methods may be embodied using transistors, logic gates, and electrical circuits, such as application specific integrated circuit. 
     Although the present disclosure has been described with an exemplary embodiment, various changes and modifications may be suggested to one skilled in the art. It is intended that the present disclosure encompass such changes and modifications as fall within the scope of the appended claims.