Splitting frequency resources for transfer of control signals and data signals in communication system sc-fdma

TECHNICAL FIELD

The present invention relates generally to wireless communications, and more particularly to a multiple access communication system with frequency division of a single carrier (SC-FDMA), and is further considered in the development of long term evolution (LTE) enhanced universal terrestrial radio access (E-UTRA ) Third Generation Partnership Project (3GPP).

Description of Related Art

More particularly, the present invention considers partitioning resources allocated for transmission of control and data signals in a SC-FDMA communication system. This invention assumes the uplink (UL), the proper transmission of signals from mobile subscriber units (UE) to a serving base station (or Node B). UE, which is also commonly referred to as terminal or mobile station may be stationary or mobile and may be a wireless device, a cellular telephone, a personal computer device, a wireless modem card, etc. Node B is generally a fixed station and may be called a base transceiver station BST, access point, or some other terminology.

Different types of signals should be maintained for proper functionality of the communication system. In addition to data signals, which carry the information content of the transmission, it is also necessary to transmit control signals from the subscriber units to their serving Node B in uplink UL and from the Node B to the subscriber units on the downlink (DL) to ensure proper transmission of data signals. The downlink refers to the communication link from the Node B to the UE. These control signals will be described in detail hereinafter with emphasis on the UL.

It is assumed that the UE transmit data signals (or data packets) on a physical shared channel uplink (PUSCH). As shown in Figure 1, the channel PUSCH during the same period may be used a plurality of UE, with each UE using a different part of the operating bandwidth (BW), in order to avoid mutual interference (frequency domain multiplexing (FDM)). UE1 110 transmits a bandwidth BW 120 while UE2 130, UE3 150, and UE4 170 are transmitted in frequency bands BW 140, BW 160 and BW 180, respectively. An exception is the use of multiple access techniques with spatial separation (SDMA), where a plurality of UE can share the same RB in one subframe to transmit its packet data channel PUSCH.

It is assumed that a Node B transmits data signals (or data packets to the UE on a physical shared channel outgoing line (PDSCH). Similarly, as the PUSCH, the PDSCH within the same period of time may be used by multiple subscriber units by FDM.

Sending data via PUSCH and PDSCH may be scheduled by the Node B through the appointment of UL scheduling or DL, respectively, using the physical downlink control channel (PDCCH) or they can be pre-configured for periodic implementation (persistent scheduling PUSCH or PDSCH transmission). Using the PDCCH signaling data on PUSCH or PDSCH, generally speaking, may occur in each subframe as determined by the scheduler Node B. Accordingly, the scheduling of such transmissions commonly called dynamic.

To avoid excessive PDCCH overhead in, some PUSCH and PDSCH transmissions may be configured to periodically implement a predetermined portion of the operating bandwidth. Such a plan is called a constant. 2 is shown the concept of persistent scheduling, when the original packet transmission 210 occurs periodically every assignment of slots 220. The persistent scheduling is typically used for communication services having relatively small bandwidth requirements per transmission period but should be provided a plurality of UE, which makes dynamic scheduling channel PDCCH inefficient due to the associated overhead in DL communication system. One of the typical examples of such services is an IP telephony (VoIP).

It is assumed that in response to the PUSCH and the PDSCH are transmitted signal or negative acknowledgment positive, ACK or NAK, respectively, transmitted to the UE or from the UE, respectively. Since the present invention contemplates the UL communication system, attention will focus on signals ACK / NAK, transmitted by the UE in response to a PDSCH transmission. ACK / NAK signaling is required for using hybrid automatic retransmission request (HARQ), wherein upon receiving a NAK packet of data retransmitted after receiving the ACK and transmits a new data packet.

Because PDSCH scheduling UE to the DL can be dynamic or permanent transfer of ACK / NAK signals from the UE is correspondingly dynamic or permanent. In the latter case, like the PDSCH transmission, ACK / NAK transmission from the UE is periodic.

In addition to periodic and dynamic signaling ACK / NAK UE can periodically transmit other control signals. One example of such signals is channel quality indication (CQI). It is assumed that the CQI is periodically transmitted to the serving Node B to inform about the state of the channel, which can be represented as the ratio of signal to interference and noise ratio (SINR), that the UE experiences in the DL. There may also be other periodic transmissions of control signals other than CQI or ACK / NAK.

Thus, it is assumed that the UL of the communication system to support dynamic and persistent PUSCH transmission, ACK / NAK transmission in response to dynamic or persistent PDSCH transmission, CQI transmission and possibly other control signaling. It is assumed that CQI transmission, and permanent PUSCH ACK / NAK in response to the constant PDSCH occur periodically until they are disabled by the Node B or until the period corresponding to the transmission configurations. These signals ACK / NAK and CQI together will be referred to as a physical uplink control channel (PUCCH). In the PUCCH channel can be transmitted periodically and other control signals.

It is assumed that the PUSCH transmission occur during the transmission time period (TTI), which corresponds to one subframe. 3 is a block diagram illustrating a structure of a subframe 310, assumed in the exemplary embodiment, the disclosed invention. This sub-frame includes two slots. Each slot 320 includes seven symbols and each symbol 330 comprises a cyclic prefix (CP) for mitigating interference due to channel propagation effects. Transmission signals in these two slots may be in the same range as in the different bands of the operating bandwidth.

The typical structure of a subframe in the block diagram in Figure 3 the middle symbol in each slot carries transmission of reference signals (RS) 340, also known as pilot signals, which are intended for different purposes, including providing a channel estimation which allows for coherent demodulation of the received signal. The number of symbols for RS transmission UL subframe may be different for PUSCH, PUCCH with ACK / NAK transmission and the PUCCH with CQI transmission. For example, in case of ACK / NAK PUCCH transmissions middle three symbols in each slot may be used for RS transmissions (the remaining symbols are used for transmitting ACK / NAK); whereas in case of CQI PUCCH transmissions of the second and sixth symbols in each slot may be used for RS transmission (and the remaining symbols are used for CQI transmission). This is also shown in Figure 9, 10 and 11, which will be described hereinafter.

It is assumed that the transmission bandwidth is composed of segments of frequency resources, which will be called resource blocks (RB). A typical embodiment of the invention assumes that each RB includes 12 SC-FDMA sub-carriers, and the UE is allocated a plurality of N successive RB 350 for PUSCH transmission and one RB for PUCCH transmission. Nevertheless, these figures are for illustration only and do not limit the invention.

Although it is not the material of the disclosed invention, a typical block diagram of a transmitter structure for the PUSCH is illustrated in Figure 4. If the UE has both data bits and control (ACK / NAK, CQI, etc.) for transmission in the same PUSCH sub-frame, then the ACK / NAK transmission, some data bits (such as parity bits case of turbo coding) may be put out and replaced by bits of ACK / NAK. Thus, we avoid simultaneous PUSCH and PUCCH transmission from a UE, a single-carrier property is preserved. Coded CQI bits 405 (if they exist) and coded data bits 410 are multiplexed 420. If necessary also transmit bits and ACK / NAK on PUSCH, some data bits (or possibly CQI bits) are punctured to accommodate there bits ACK / NAK 430. Next, the discrete Fourier transform (DFT) 440 combined data bits and control bits are selected sub-carriers 450 corresponding to the assigned transmission bandwidth 455, performs inverse fast Fourier transform (IFFT) 460, and finally to the transmitted signal 490 applies a cyclic prefix (CP) 470 and filter 480.

It is assumed that the UE applies the signal with zeros in addition subcarriers used by other UE, and guard subcarriers (not shown). Moreover, for brevity, additional transmitter circuitry elements, such as a digital to analog converter, analog filters, amplifiers, and transmitter antennas are known in the art, are not shown in Figure 4. Similarly, omitted for brevity encoding process for the data bits and CQI bits, and a modulation process of the transmitted signals, is well known in the art.

Receiver operations are carried out, reverse (complementary) transmitter operations. Conceptually, this is shown in Figure 5, where the operations are applied, return to those made 4. As is known in the art (not shown for brevity), an antenna receives an analog high-frequency (RF) signal and after further processing (such units as filters, amplifiers, reducing the frequency converters and analog-to-digital converters) the received digital signal 510 passes through a analyzing the time domain 520 and the CP is removed 530. Further, the receiving device applies the Fourier transform FFT 540, selects 545 the sub-carriers 550 used by the transmitter, applies an inverse digital Fourier Transform IDFT 560 extracts the bits ACK / NAK and sets the corresponding bit in the data erase and 570 580 demultiplexes the CQI bits 590 and data bits 595. As with the transmitter, well known in the art, the functions of the receiving device, such as channel estimation, demodulation, and decoding are not shown for brevity and they are not material to the invention.

A block diagram of the structure of the transmission channel PUCCH (ACK / NAK, CQI) shown in Figure 6, it also is not the material of the described invention. It is assumed that transmission is performed by modulating sequences 610 based CAZAC (Constant Amplitude Zero Autocorrelation). Similarly, it is assumed that transmission is performed by means of unmodulated RS sequences 610 based CAZAC. 620 subcarriers are selected, the corresponding frequency band assigned for transmission, and sequence elements located in selected subcarriers 630 channel PUCCH. Performs inverse fast Fourier transform (IFFT) 640, the result is subjected to cyclic shift in the time domain 650, and finally to the transmitted signal 680 applies a cyclic prefix (CP) 660 and filtering 670. As compared with the structure of the transmitter 4 PUSCH main difference is the lack DFT block (because it is assumed, although this is not required that the CAZAC sequence based on the displayed immediately to the frequency domain to avoid the DFT operation) and the application of the cyclic shift 650. In addition, the signals ACK / NAK, RS, and possibly, CQI can be used for protection of the Walsh code set of corresponding symbols in the subframe (3).

When receiving the CAZAC sequence based on the inverse operations are carried out, as shown in Figure 7. The received signal 710 passes through a time domain analysis 720 and the CP is removed 730. Further, the cyclic shift is restored 740 applies FFT 750 are selected subcarriers 760 used by the transmitter 765 applies 780 the correlation with the replica 770 based on the CAZAC sequence and the data output 790. These output may be sent to the channel estimation unit, such as a time-frequency interpolator, in case of RS, or can be used for detecting the transmitted information, in case the CAZAC-based sequence is modulated by information bit ACK / NAK or CQI.

An example of CAZAC-based sequences is given by the following equation (1):

(1)

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In equation (1) L - the length of the CAZAC sequence, n - the index of a particular element of the sequence n = {0,1,2 ..., L-1}, and finally, k - the index of the sequence itself. For a given length L, there L-1 distinct sequences, provided that L - is a prime number. Thus, an entire family of sequences is defined as the index k varies in the range {1,2, ..., L-1}. However, the CAZAC sequences, are used in the signal transmission channel PUCCH, not necessarily generated using this exact expressions given above, as discussed further below.

For CAZAC sequences of length L, expressed by the prime number, the number of sequences is equal to Ll. Since it is assumed that the ranges RB contain an even number of sub-carriers, with 1 RB includes 12 sub-carriers, the sequences used to transmit the ACK / NAK and RS, may be generated in the frequency or time domain, or by truncating the sequence CAZAC, built on too long simple number (length) L (such as 13), or by extending the sequence CAZAC, built on too short a prime number (length) L (such as 11), by repeating its first element (or multiple primary elements) at its end (cyclic extension ), although the resulting sequences thus do not meet the definition of CAZAC sequences. Alternatively, CAZAC sequences can be generated through a computer search for sequences satisfying the properties of CAZAC.

Different cyclic shifts of the same CAZAC sequence provide orthogonal CAZAC sequences. Therefore, different cyclic shifts of the same CAZAC sequence can be allocated to different UE in the same RB for transmission to RS, ACK / NAK or CQI, and multiplexing the orthogonal signals is achieved UE. This principle is shown in Figure 8.

To different CAZAC sequences 810, 830, 850, 870, are generated by different cyclic shifts 820, 840, 860, 880, respectively, of the same root CAZAC sequence, are orthogonal, the cyclic shift value 890 should exceed the value of D delay spread Distribution in the channel (which includes a time uncertainty error and filter effects overflow). If - the duration of a single character, the number of cyclic shifts is equal to the lower of the mathematical integer part of the relationship. The granularity of the cyclic shift is one element of the sequence CAZAC. For CAZAC sequences of length 12, the number of possible cyclic shifts is 12 and for symbol duration of about 66 microseconds (14 symbols in a 1 millisecond sub-frame), the time separation of consecutive cyclic shifts is about 5.5 microseconds.

<IMG>

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Configuration parameters CQI signaling, such as the transmission RB and the transmission sub-frame is made for each UE through higher layer signaling, and this configuration is valid for a longer time than the subframe. Likewise parameters ACK / NAK transmission according to the persistent scheduling PDSCH and PUSCH persistent transmission parameters (such as the RB and sub-frame) remains the same over comparable time periods.

A consequence of SC-FDMA signaling is that the transmission bandwidth must be continuous. In order to avoid fragmentation for PUSCH transmissions, PUCCH transmissions should be placed at the two ends of the operating bandwidth. Otherwise, if both sides PUCCH transmission bandwidth remains available RB, they can not be used in the same UE for PUSCH transmission, to thereby preserve the properties of a single carrier transmission.

Moreover, as PUCCH transmission includes periodic CQI transmission, periodic ACK / NAK transmission, and dynamic ACK / NAK transmission, it is necessary to determine the proper ordering for the corresponding RB at the two ends of the operating bandwidth.

Furthermore PUCCH transmission persistent scheduling PUSCH transmissions also results in similar bandwidth characteristics of the filling, as in the case of a channel PUCCH.

SUMMARY OF THE INVENTION

The present invention has been made to solve the problems listed above that arose in the prior art and the present invention provides an apparatus and method for allocating resources for transmission of control and data signals from subscriber units to their serving Node B.

Additionally, the present invention determines the partitioning RB, allocated to PUCCH transmissions among RB, used for CQI transmissions, periodic ACK / NAK transmissions PDSCH according to the persistent scheduling and dynamic ACK / NAK transmissions according to dynamic scheduling PDSCH.

Additionally, the present invention maximizes the bandwidth utilization for PUSCH transmissions while at the same time places the PUCCH transmission.

Additionally, the present invention allows for permanent PUSCH transmission, and thus is not permitted bandwidth fragmentation.

Additionally, the present invention contributes to the achievement of reception reliability requirements transmission, particularly for control signals.

Additionally, the present invention informs the UE of the first RB, which is available for dynamic ACK / NAK transmissions.

According to one embodiment of the invention provides a method of frequency allocation of segments (resource block (RB)), used by control signals with a periodic transmission, by control signals from the dynamical transfer and data signals.

According to another embodiment of the present invention provides a method of frequency allocation of segments used by control signals with a periodic transmission of control signals to the dynamic transmission data signals with a periodic transmission signals to the dynamic transmission data.

According to another embodiment of the present invention are an apparatus and method allowing a subscriber unit having an acknowledgment signal in response to the data signal transmitted thereto serving Node B according to the corresponding scheduled appointment, determine the first frequency segment, suitable for transmitting the acknowledgment signal.

According to another embodiment of this invention provides an apparatus and method for allowing the serving Node B to inform the subscriber units having the handshaking signals in response to respective data signals transmitted by them to the serving Node B according to the corresponding scheduled destinations, the first frequency segment, suitable for transmitting these heartbeats.

BRIEF DESCRIPTION OF THE DRAWINGS

All previously mentioned and other aspects, features and advantages of the invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:

Figure 1 - a view showing a partition of the operating bandwidth for an orthogonal transmission of signals from multiple UE through frequency division multiplexing (FDM);

2 - a diagram showing the concept of a constant (periodic) data signal transmission from the UE;

Figure 3 - a block diagram showing a typical structure of a subframe for a communication system SC-FDMA;

4 - block diagram showing a first exemplary SC-FDMA transmitter for multiplexing data bits, CQI bits, and bit ACK / NAK transmission in the subframe;

5 - a block diagram showing a typical SC-FDMA receiver for demultiplexing data bits, CQI bits, and bits of ACK / NAK in subframe reception;

Figure 6 - a block diagram showing a typical transmitter for CAZAC sequence based on the frequency domain;

7 - is a block diagram showing a typical receiver for a CAZAC-based sequence in the frequency domain;

Figure 8 - is a block diagram showing a typical construction of orthogonal CAZAC-based sequences through the application of different cyclic shifts of a root CAZAC-based sequence;

9 - diagram showing a typical partitioning of resource blocks for transmission CQI, ACK / NAK, and data signal;

10 - a diagram showing a first exemplary partitioning of resource blocks for transmission CQI, persistent and dynamic transmission ACK / NAK, and persistent and dynamic data signal transmissions; and

11 - chart showing the second exemplary partitioning of resource blocks for transmission CQI, persistent and dynamic transmission ACK / NAK, and persistent and dynamic data signal transmissions.

DETAILED DESCRIPTION OF THE INVENTION

The invention will be described more fully with reference to the accompanying drawings. This invention may, however, be embodied in many different forms and should not be inferred that it is limited to embodiments provided herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the possibilities of this invention for those skilled in the art.

Furthermore, although the present invention contemplates the communications system of multiple access, frequency division of a single carrier (SC-FDMA), it also applies to all FDM system in general, and more particularly, to OFDMA, OFDM, FDMA, DFT-extended OFDM, DFT -extension OFDMA, single-carrier OFDMA (SC-OFDMA), and single-carrier OFDM.

System ideas and methods of these embodiments of the invention solve the problem concerning the need to maximize the use of available bandwidth for the transmission of signals from the subscriber units to the serving Node B, to ensure achievement of a predetermined level of reliability of transmission reception and inform the UE device sends an acknowledgment of the first frequency segment (or resource block (RB)), suitable for the transmission of these signals.

As discussed in the preceding description of the prior art, some signals in the UL have a periodic nature and the corresponding allocation of resource blocks (RB), or the frequency segments in each sub-frame can be predetermined for a relatively long period of time comparable to the duration of the subframe. These signals include the CQI, ACK / NAK, associated with persistent PDSCH transmissions, and the persistent PUSCH transmission. As explained in detail hereinafter, a number of reasons, including the need to prevent the fragmentation of bandwidth and at the same time maintaining support transmission on a single carrier, it is desirable to place these signals around two edges (ends) of the operating bandwidth.

In addition to dynamically scheduled PUSCH transmissions, other signals that may require a variable number of resource blocks RB per subframe include ACK / NAK in response to dynamic PDSCH transmission (dynamic ACK / NAK). These blocks RB for dynamic transmissions ACK / NAK, therefore, should be placed after the blocks for dynamic PUSCH transmissions, since the last block RB, selected for periodic PUCCH and PUSCH transmissions, and be placed in the inner side portion of the operating bandwidth (BW).

Partitioning periodic PUCCH transmissions, such as CQI transmission, and dynamic ACK / NAK transmission is considered first in a typical situation shown in Figure 9. It is assumed that the CQI transmission from a UE is performed on opposite ends of the operating bandwidth BW in the first slot 910A and second slot 910B. According to the present invention, blocks RB, used for dynamic ACK / NAK transmission by another UE in the first slot 920A and second slot 920B, located in the inner side of the blocks RB, used for transmitting CQI, adjacent to the blocks RB, used for dynamic PUSCH transmission in the first slot 930A and second slot 930B of the sub-frame and disposed outwardly from them.

Since the number of UE with dynamic PDSCH transmissions in a sub-frame may vary, the number of blocks RB, used by the corresponding dynamic ACK / NAK transmission channel PUCCH, and may vary from subframe to subframe (although shown in Figure 9, only one block RB for dynamic ACK transmission / NAK). Such changes can not be taken into account in advance, as it is assumed that the Node B scheduler functional for a certain number of assigned dynamic PDSCH transmissions per sub-frame.

Since it is assumed that each UE with dynamic ACK / NAK transmission knows allowable range multiplexing in one block RB (this parameter can be broadcasted to all the serving Node B) and its location relative to the ACK / NAK transmission from the other UE (either explicit signals serving Node In either indirectly, for example via PDCCH index, used for routine purposes), then the UE can know which RB and which block the resource block (such as the selection of the cyclic shift based CAZAC sequence) to use it. For example, if the range of ACK / NAK multiplexing is 18 and the relative order of a UE for ACK / NAK transmission is 20, then the UE for its ACK / NAK transmission using the second resource block in the second RB, used for transmission of dynamic ACK / NAK. More generally, if the range of ACK / NAK multiplexing block RB is M, and the relative order of a UE dynamic ACK / NAK transmission is P, this UE may use the resource:

mod (P, M),

in the block number RB

Q = ceil (P / M),

where mod (x, y) is x minus (n multiplied by y), the number n is equal to floor (x divided by y). Operation "floor" of his rounds to the nearest whole number, then the operation "ceil" rounds to its nearest whole number.

Accommodation blocks RB for dynamic ACK / NAK transmission on the inner side of the operating frequency band immediately after blocks RB, used for periodic transmissions PUCCH (such as CQI), for which the number of RB per subframe is fixed for longer periods of time (when they are located immediately after (and outwardly from) blocks RB, used for dynamic PUSCH transmissions), avoiding fragmentation or waste of bandwidth due to the occurrence of unused blocks RB. Otherwise, if the blocks RB for dynamic ACK / NAK transmission is placed before block RB for periodic transmissions PUCCH and the outer side of the operating frequency band could be caused fragmentation of bandwidth in a situation where the number of RB for dynamic ACK / NAK transmission changes from subframe to subframe.

Instead, if these blocks RB are divided between periodic and dynamic PUCCH transmissions, as illustrated in Figure 9, any change in the number of blocks RB, used for the transmission of dynamic ACK / NAK, may, without causing any problems, be included in plan a dynamic PUSCH transmissions in the remaining blocks RB without causing any fragmentation or RB unused bandwidth as said first blocks can be viewed simply as an extension of the latter and vice versa. The serving Node B knows how many blocks RB need in each subframe for transmission of dynamic ACK / NAK, and it can appropriately allocate blocks RB for PUSCH transmission, without compromising bandwidth fragmentation.

Another reason for placing blocks RB for dynamic ACK / NAK transmission in the inner side of the blocks RB, selected for periodic PUCCH transmissions, is that the said first blocks may become available for PUSCH transmission after a certain number of subframes line UL. This occurs in a situation where subframes line DL to multicast broadcast traffic, because in this case there is no ACK / NAK transmission in corresponding subsequent subframes UL (during multicast broadcast subframes DL assumes no unicast transmissions PDSCH, requiring a response ACK / NAK) . It is not always possible to be done because of the properties of a single carrier if blocks RB for ACK / NAK transmission is not adjacent to the blocks RB gear PUSCH.

Another reason why blocks RB for dynamic ACK / NAK are placed in the inner portion of the bandwidth between the blocks for dynamic ACK / NAK and periodic PUCCH transmissions, is that from the first generally requires a greater degree of reliability than that of the latter. Transmissions in interior blocks RB largely avoided band interference caused by transmissions in adjacent frequency bands, which may be considerably more powerful, and therefore ACK / NAK signals are better protected against such interference if that serves interior blocks RB.

Generalization RB allocating blocks, illustrated in Figure 9 is shown in Figure 10, where in addition to the blocks RB for CQI, dynamic ACK / NAK, and dynamic PUSCH transmissions, are also included in the consideration and blocks RB for persistent ACK / NAK transmissions and permanent PUSCH. Periodic transmission can be interchanged or mixed. Such an alternative ordering for periodic transfers is shown in Figure 11.

These blocks RB for permanent transmission ACK / NAK 1010A and 1010B or blocks RB for permanent transmission PUSCH 1020A and 1020B are located outwardly from blocks RB for dynamic transmissions ACK / NAK 1030A and 1030V, which again are adjacent to each other and outwardly from the RB blocks for dynamic transmission PUSCH 1040A and 1040B, as soon as they may vary from sub-frame to sub-frame in an unpredictable manner. Thus blocks RB for PUCCH transmission of periodic and permanent PUSCH transmissions may also vary from subframe to subframe, but these changes occur in a predetermined manner.

Furthermore, although in Figure 10 blocks RB for transmitting ACK / NAK, according to the persistent scheduling PDSCH, located inwardly of the blocks RB for the CQI transmission in the two slots, but this is not necessary, and blocks of said second may be positioned with the inner side of the first one of the two slots. Additionally, any transmission of these signals may be enclosed in only one slot or can extend after one subframe.

Figure 11 illustrates the same principle as in Figure 10, with the only difference in the relative positions of the permanent PUSCH transmissions 1110A and 1110V and CQI transmissions 1120A and 1120B. Transmitting CQI, generally require a greater degree of reception reliability than persistent transmission PUSCH, as the latter benefit from the use HARQ, however if we avoid placing CQI in blocks RB at the edges of the operating bandwidth, it protects the CQI from the possible-of-band interference and as consequently, increases the reliability of its reception.

In both figures, 10 and 11, blocks RB for persistent ACK / NAK transmission are located outwardly from blocks RB for dynamic ACK / NAK transmission, but with the inner side of the RB blocks for CQI transmissions or persistent PUSCH transmissions. In this case, if the previous subframe was no scheduling PDSCH, as is the case when the sub-frame carries traffic multicast broadcast, in the subsequent subframe UL does not make any transmissions ACK / NAK, and then those blocks RB, which otherwise would be used by subscriber units UE transmission for ACK / NAK, can be used for PUSCH transmission.