JP2009171025A - Mobile station apparatus, base station apparatus, and wireless communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To highly accurately estimate a channel even in a communication format with restriction on the disposition of reference signals and to improve a reception performance in a low SNR environment or a high speed movement environment. <P>SOLUTION: With respect to up signals from the mobile station apparatus to the base station apparatus in the wireless communication system, in the transmission symbol LB of a plurality of transmission slots continuously arranged timewise, a data symbol and the reference signal are mapped and disposed for each resource block RB which is a unit of a frequency domain divided into a plurality of pieces. In this case, when performing frequency hopping, the reference signal is disposed in the same frequency domain as the data symbol at least inside one slot, and in each slot, the reference signal is disposed to the resource block RB for which the data symbol is mapped in the adjacent slot as well in addition to the resource block RB for which the data symbol is mapped in the present slot. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a mobile station device and a base station device used for mobile communication and the like, and a radio communication system.

  In a wireless communication system for mobile communication such as a cellular phone, it has been studied to improve a transmission rate by various multiplexing techniques. In recent wireless communication systems for mobile communication, frequency multiplexing schemes such as OFDM (Orthogonal Frequency Division Multiplexing), which are also used in, for example, wireless LAN and digital terrestrial broadcasting, are being studied. By adopting the frequency multiplexing method, it is possible to suppress deterioration in transmission quality due to fading or the like, and to increase the speed and quality of wireless transmission. In addition, in frequency multiplexing systems such as OFDM, frequency hopping (FH) may be employed in order to improve fading resistance. Frequency hopping is a technology that prevents the use of only a specific frequency region by changing the frequency region to be used among a plurality of frequency regions, and suppresses performance degradation due to frequency selective fading. .

  As a prior art of a wireless communication apparatus adopting frequency hopping, there is one disclosed in Patent Document 1 (Japanese Patent Laid-Open No. 2007-142602). The prior art of Patent Document 1 shows a technique for improving a channel estimation value by using a plurality of pilot signals arranged in the same frequency band.

  FIG. 17 shows a frame format assumed in the prior art. Here, the modulation method is OFDM (Orthogonal Frequency Division Multiplexing), and one transmission unit (Transmission Time Interval: TTI) is composed of a packet synchronization acquisition sequence, a channel estimation sequence, and a data payload. To do. In addition, frequency hopping is performed for three bands A, B, and C, and in the channel estimation sequence, two known signals (pilot signals) are arranged in each band, as shown in FIG. And

  FIG. 18 is a block diagram of a channel estimation / equalization processing unit in a conventional receiver. First, the received signal is converted into the frequency domain by FFT (Fast Fourier Transform) before the channel estimation / equalization processing unit. Next, a channel estimation sequence is extracted from this, and is multiplied by a reference channel estimation sequence prepared in advance on the receiver side to obtain a correlation value. Subsequently, the obtained correlation value is averaged with the correlation values of adjacent subcarriers. This makes it possible to obtain a correlation value that has fluctuated due to frequency selective fading.

  The above processing is performed on all channel estimation sequences, and finally interpolation processing is performed on two channel estimation sequences (A1 and A2, B1 and B2, C1 and C2) mapped to the same band.

  Here, as an interpolation processing method, it is possible to reduce the correlation error due to noise power superimposed on the channel estimation sequence by averaging zero-order interpolation, that is, averaging two correlation values (determining the internal component). Become. This zero-order interpolation is particularly effective when the received signal has a low signal-to-noise power ratio (SNR) and the received signal is affected by low-speed fading.

  As another interpolation processing method, two correlation values are linearly interpolated, that is, a linear interpolation value of the correlation value is obtained (external division is obtained), phase rotation correction is performed, and fading received by the subsequent payload portion Can be estimated with high accuracy. This primary interpolation is an essential process particularly when the received signal is affected by high-speed fading.

By multiplying the payload portion by the channel estimation result obtained by the above processing, it is possible to correct amplitude and phase fluctuations due to fading.
JP 2007-142602 A

  However, in the conventional technology described above, two or more pilot signals are required on the time axis in one transmission unit (1 TTI), and there is only one pilot signal in one TTI. There is a problem that it cannot be applied. For example, in the uplink (Uplink) frame format of the next generation mobile communication standard being studied in 3GPP Long Term Evolution (hereinafter referred to as LTE), when viewed in the time axis direction, one slot contains 7 transmission symbols. In addition, in the case where 1 TTI is configured by two slots, a configuration in which only one reference signal serving as a pilot signal is arranged at the center of each slot (7 symbols) has been studied.

  In such a frame format, when frequency hopping is performed in slot units, when viewed in the frequency direction, only one reference signal is arranged in 1 TTI in one frequency domain unit to which data symbols and the like are mapped. The prior art cannot be applied. For this reason, there is a problem that noise suppression by 0th-order interpolation and phase rotation correction by 1st-order interpolation cannot be performed, and high-accuracy channel estimation cannot be performed. Therefore, reception performance deteriorates when the mobile station apparatus is moving at high speed or when the SNR is low (for example, when the mobile station apparatus is at the cell edge). In particular, the problem at the time of high-speed movement is serious. In the worst case, even if techniques such as retransmission control and adaptive modulation / demodulation are used, reception may not be possible at all.

  The present invention has been made in view of the above circumstances, and enables high-accuracy channel estimation even in a communication format in which the arrangement of reference signals is limited, and improves reception performance in a low SNR environment or a high-speed mobile environment. It is an object of the present invention to provide a mobile station device and a base station device that can perform the above-described operation, and a wireless communication system.

According to the present invention, first, in a first transmission slot and a second transmission slot that are continuously arranged in time, a data symbol of the first transmission slot and a data symbol of the second transmission slot are A mobile station apparatus of a radio communication system using communication formats that can be arranged in different frequency regions, a control channel receiving unit that receives a control channel notified from a base station apparatus, and data allocation included in the control channel A reference signal determining unit that determines an arrangement of reference signals based on the information; a reference signal generating unit that generates the reference signal according to the determined arrangement; and a transmission signal that includes the reference signal according to the data allocation information. And a transmission unit for transmitting to the base station apparatus, wherein the data allocation information is data of the first transmission slot. And data allocation related to frequency hopping in which data symbols of the second transmission slot are arranged in different frequency regions, and the reference signal determination unit is configured to transmit the first transmission in the first transmission slot. The reference signal is arranged in a frequency region where a data symbol of the slot is arranged and a frequency region where a data symbol of the second transmission slot is arranged, and in the second transmission slot, the reference signal of the second transmission slot is arranged. There is provided a mobile station apparatus that arranges the reference signal in a frequency domain in which data symbols are arranged and in a frequency domain in which data symbols of the first transmission slot are arranged.
Thereby, even in a communication format in which the arrangement of reference signals is restricted, two reference signals are arranged in the same frequency region in two adjacent transmission slots, so in the base station apparatus of the communication partner station, For example, interpolation processing such as noise suppression by zero-order interpolation and phase rotation correction by primary interpolation can be performed on the channel estimation value. Therefore, even when frequency hopping is performed, the ability to follow fading fluctuations can be improved, and high-accuracy channel estimation is possible. Therefore, reception performance can be improved in a low SNR environment or a high-speed moving environment.

The present invention also provides the mobile station apparatus according to the second aspect, wherein the reference signal generation unit transmits the reference signal so as to be code-multiplexed with another radio communication apparatus using the same radio communication system. Includes what to generate.
Thus, in addition to the frequency region in which data is arranged in the transmission slot, the reference signal assigned to another wireless communication device when the reference signal is arranged in the frequency region in which data is arranged in the adjacent transmission slot. When the frequency regions overlap with each other, each reference signal can be separated and extracted by code multiplexing.

Third, the present invention is the above mobile station apparatus, wherein the reference signal generation unit uniquely determines the content of the reference signal by frequency domain arrangement information in the data allocation information. Including what is supposed to be.
As a result, the reference signal can be determined and generated according to frequency domain arrangement information such as a hopping pattern when performing frequency hopping.

In addition, according to the fourth aspect of the present invention, in the mobile station apparatus described above, the reference signal determination unit includes all frequency regions in which data in the first transmission slot can be arranged, and the second The reference signal is included in all frequency regions in the transmission slot where data can be allocated.
As a result, two reference signals are arranged in the same frequency region in two adjacent transmission slots, and interpolation processing such as zero-order interpolation and primary interpolation can be performed in the base station apparatus of the communication counterpart station. Therefore, high-accuracy channel estimation is possible, and reception performance can be improved in a low SNR environment or a high-speed moving environment. Further, by using the reference signal arranged in the entire frequency region, it is possible to measure the reception quality in the entire frequency region without using an uplink quality measurement channel or the like.

Fifth, according to the present invention, in the first transmission slot and the second transmission slot that are continuously arranged in time, the data symbol of the first transmission slot and the data symbol of the second transmission slot are A base station apparatus of a wireless communication system that uses communication formats that can be arranged in different frequency regions, a receiving unit that receives a signal transmitted from a mobile station apparatus, and a reference signal is extracted from the received received signal A reference signal extraction unit; a channel estimation unit that performs channel estimation of a transmission path using the reference signal; and an interpolation unit that interpolates channel estimation values based on the channel estimation in a plurality of transmission slots. In the first transmission slot, a frequency region in which data symbols of the first transmission slot are arranged and the second transmission slot The reference signal is arranged in a frequency region in which data symbols are arranged, and in the second transmission slot, in the frequency region in which the data symbols of the second transmission slot are arranged and in the first transmission slot When the reference signal is arranged in the frequency domain in which the data symbols are arranged, the channel estimation value of the reference signal in the same frequency domain in the first transmission slot and the second transmission slot is zero-order interpolated. Alternatively, a base station apparatus that performs linear interpolation is provided.
As a result, even in a communication format in which the arrangement of reference signals is limited, two reference signals are arranged in the same frequency region in two adjacent transmission slots. For example, noise due to zero-order interpolation regarding channel estimation values By performing interpolation processing such as suppression and phase rotation correction by primary interpolation, it is possible to improve the followability to fading fluctuations even when performing frequency hopping. Accordingly, since channel estimation with high accuracy is possible, reception performance can be improved in a low SNR environment or a high-speed moving environment.

In addition, according to the present invention, sixthly, in the above base station apparatus, reference signals in the same frequency domain in the first transmission slot and the second transmission slot are different from each other using the same radio communication system. The channel estimation unit is code-multiplexed between wireless communication apparatuses, and the channel estimation unit references the channel estimation value of the code-multiplexed reference signal of the first transmission slot and the code-multiplexed second transmission slot Includes determining the channel estimate of the signal.
As a result, even when reference signals transmitted from a plurality of mobile station apparatuses are code-multiplexed, it is possible to obtain each channel estimation value and to demodulate data symbols from each mobile station apparatus It becomes.

Further, according to the present invention, seventhly, in the above base station apparatus, an uplink quality measuring unit that measures uplink quality from the mobile station apparatus to the base station apparatus based on the received signal, A data allocation determining unit that determines data allocation related to frequency hopping in which data symbols of the first transmission slot and data symbols of the second transmission slot are arranged in different frequency regions based on quality; and the determined data allocation And a control channel transmission unit that generates a control channel having information and transmits the information to the mobile station apparatus.
As a result, when frequency hopping is performed, a control channel having data allocation information including frequency domain arrangement information such as a hopping pattern according to uplink quality can be generated and notified to the mobile station apparatus. At this time, data allocation information that enables data arrangement such that two reference signals are arranged in the same frequency region in two adjacent transmission slots is generated.

In addition, according to the present invention, in the eighth aspect, in the above base station apparatus, the uplink quality measurement unit includes all frequency regions in which data in the first transmission slot can be arranged, and the second When the reference signal is arranged in all the frequency regions in which data can be arranged in the transmission slots, the uplink quality is measured using the reference signals in all frequency regions of the received signal Including what to do.
Thereby, by using the reference signal arranged in the entire frequency region, it is possible to measure the reception quality in the entire frequency region without using an uplink quality measurement channel or the like.

Ninthly, in the first transmission slot and the second transmission slot, which are continuously arranged in time, the present invention provides a data symbol of the first transmission slot and a data symbol of the second transmission slot. A mobile station apparatus of a radio communication system using communication formats that can be arranged in different frequency regions, a control channel receiving unit that receives a control channel notified from a base station apparatus, and data allocation included in the control channel A transmission unit that generates a transmission signal including a data symbol and a reference signal according to the information, and transmits the transmission signal to the base station apparatus, wherein the data allocation information includes a predetermined transmission slot including the first transmission slot and the second transmission slot. In one transmission unit with a number of transmission slots, the data symbol of the first transmission slot within this transmission unit. Hopping availability information for instructing applicability of Intra-TTI hopping in which data symbols of the second transmission slot are arranged in different frequency domains, and the transmission unit includes data symbols in the frequency domain according to the hopping availability information and Provided is a mobile station apparatus that arranges reference signals.
As a result, the presence / absence of Intra-TTI hopping operation can be switched based on the hopping availability information notified from the base station apparatus. Appropriate performance can be obtained according to the conditions. Therefore, reception performance in a high-speed moving environment can be improved.

Tenth, the present invention relates to a data symbol of the first transmission slot and a data symbol of the second transmission slot in the first transmission slot and the second transmission slot that are continuously arranged in time. A base station apparatus of a wireless communication system that uses a communication format that can be arranged in different frequency regions, the receiving unit that receives a signal transmitted from a mobile station apparatus, and based on cell environment information held in advance, In one transmission unit with a predetermined number of transmission slots including the first transmission slot and the second transmission slot, the data symbol of the first transmission slot and the data symbol of the second transmission slot within this transmission unit Hopping availability determination unit that determines whether to apply Intra-TTI hopping, which is arranged in different frequency regions, and the Intra-TTI hopping Generating a control channel having the data allocation information including hopping permission information for instructing applicability of ring, to provide a base station apparatus and a control channel transmitting unit that transmits to the mobile station apparatus.
As a result, for example, whether or not intra-TTI hopping can be applied is determined based on cell environment information such as a high-speed moving environment and a low-speed moving environment, and the mobile station apparatus is instructed to set the intra-TTI hopping operation based on the hopping permission information. Therefore, the frequency hopping operation according to the cell environment can be executed, and appropriate performance can be obtained. Therefore, reception performance in a high-speed moving environment can be improved.

In the eleventh aspect of the present invention, in the first transmission slot and the second transmission slot that are continuously arranged in time, the data symbol of the first transmission slot and the data symbol of the second transmission slot are A wireless communication system using a communication format that can be arranged in different frequency regions,
A control channel receiving unit that receives a control channel notified from a base station device, a reference signal determining unit that determines an arrangement of reference signals based on data allocation information included in the control channel, and the determined arrangement according to the determined arrangement A reference signal generation unit that generates a reference signal; and a transmission unit that generates a transmission signal including the reference signal in accordance with the data allocation information and transmits the transmission signal to the base station apparatus. It defines data allocation related to frequency hopping in which data symbols of a transmission slot and data symbols of the second transmission slot are arranged in different frequency regions, and the reference signal determination unit is configured to A frequency domain in which data symbols of the first transmission slot are arranged and the second transmission slot; In the second transmission slot, the reference signal is arranged in a frequency region in which the second data slot is arranged, and in the second transmission slot, the frequency region in which the data symbol in the second transmission slot is arranged and the first transmission slot. A mobile station apparatus that arranges the reference signal in a frequency domain in which data symbols are arranged;
A receiving unit that receives a signal transmitted from the mobile station device; a reference signal extracting unit that extracts a reference signal from the received received signal; and a channel estimation unit that performs channel estimation of a transmission path using the reference signal; An interpolation unit that interpolates channel estimation values obtained by the channel estimation in a plurality of transmission slots, and the interpolation unit refers to the same frequency region arranged in the first transmission slot and the second transmission slot. A base station apparatus that performs zero-order interpolation or first-order interpolation on a channel estimation value of a signal;
A wireless communication system is provided.

According to the twelfth aspect of the present invention, in the first transmission slot and the second transmission slot that are continuously arranged in time, the data symbol of the first transmission slot and the data symbol of the second transmission slot are A wireless communication system using a communication format that can be arranged in different frequency regions,
A control channel receiving unit that receives a control channel notified from a base station apparatus, and a transmission unit that generates a transmission signal including a data symbol and a reference signal according to data allocation information included in the control channel, and transmits the transmission signal to the base station apparatus The data allocation information includes, in one transmission unit of a predetermined number of transmission slots including the first transmission slot and the second transmission slot, data of the first transmission slot within the transmission unit. Hopping availability information for instructing applicability of Intra-TTI hopping in which symbols and data symbols of the second transmission slot are arranged in different frequency domains, and the transmission unit includes data symbols in the frequency domain according to the hopping availability information and A mobile station device for arranging reference signals;
A receiving unit that receives a signal transmitted from the mobile station device, a hopping availability determination unit that determines whether to apply the Intra-TTI hopping based on cell environment information held in advance, and whether to apply the Intra-TTI hopping A base station apparatus comprising: a control channel transmission unit that generates a control channel having data allocation information including hopping availability information instructing and transmitting to the mobile station apparatus;
A wireless communication system is provided.

  Advantageous Effects of Invention According to the present invention, a mobile station apparatus and a base that can perform channel estimation with high accuracy and improve reception performance in a low SNR environment or a high-speed mobile environment even in a communication format in which the arrangement of reference signals is limited. A station apparatus and a wireless communication system can be provided.

  In the present embodiment, a configuration example of a mobile station device and a base station device used in a mobile communication system such as a mobile phone and a wireless communication system will be described in detail as an example.

(First embodiment)
FIG. 1 is a diagram showing a communication format of a wireless communication system according to the first embodiment of the present invention. Here, as an example of a radio communication system, a configuration example applicable to uplink communication studied in LTE is shown. In the uplink frame format under consideration in LTE, one slot (= 0.5 msec) is composed of 7 transmission symbols in the time axis direction, and 1 TTI (= 1.0 msec) is composed of two slots. ) Is configured. Here, transmission symbols per 1 TTI (Long Block: LB) are LB # 1 to # 14, the first slot is LB # 1 to # 7, and the second slot is LB # 8 to # 14. To do. In these transmission symbols LB, data symbols and reference signals are mapped and arranged. The data symbol includes a signal obtained by modulating data such as image data and audio data to be transmitted from the transmission device to the reception device by a modulation method such as QPSK (Quadrature Phase Shift Keying). The reference signal to be a pilot signal includes a signal determined in advance between the receiving device and the transmitting device based on a certain rule. By referring to this reference signal by the receiving device, it is possible to estimate or correct the amplitude fluctuation amount, the phase fluctuation amount, etc. that the data symbol has received on the radio propagation path. The reference signal is also called demodulation reference signal (DMRS), and is arranged in transmission symbols LB # 4 and # 11 in the center of each slot.

  In the frequency axis direction, the data symbol and the reference signal are mapped and arranged for each unit of the frequency domain divided into a plurality. Here, the unit of each frequency region is referred to as a resource block (RB), and 25 resource blocks RB # 1 to # 25 are set. These resource blocks RB are mapped in slot units and TTI units, and the reference signal is mapped in at least the same frequency region (same resource block) as the data symbols in the same slot. FIG. 1 shows an example in which data symbols and reference signals are mapped to RB # 24 and # 25 in the first slot and RB # 1 and # 2 in the second slot, respectively.

  In the first embodiment, in each slot, in addition to the resource block RB in which the data symbol is mapped in the own slot, the reference signal is also mapped in the resource block RB in which the data symbol is mapped in the adjacent slot. That is, the reference signal is arranged in the frequency domain where data symbols are arranged in at least one of the adjacent slots before and after. Thereby, the reception performance is improved.

  First, focusing on LB # 4 in which the reference signal of the first slot is arranged, in addition to RB # 24 and RB # 25 in which data symbols are mapped to the first slot, data symbols are mapped to the second slot. The reference signal is also mapped to RB # 1 and RB # 2. Similarly, focusing on LB # 11 in which the reference signal of the second slot is arranged, in addition to RB # 1 and RB # 2 in which data symbols are mapped in the second slot, data symbols are mapped in the first slot. The reference signal is also mapped to RB # 24 and RB # 25.

  With such a frame format configuration, even when frequency hopping is applied, two reference signals (LB # 4 and LB # 11) are mapped on the same resource block RB at short time intervals. It is possible to obtain a highly accurate channel estimation value by interpolating the channel estimation value obtained from both the internal and external divisions.

  The data arrangement (mapping pattern) including the data symbol and the reference signal is determined by the base station apparatus of the radio communication system based on the uplink quality information of each mobile station apparatus, and the data included in the control channel each time. The mobile station apparatus is notified and assigned by the allocation information. Specifically, the following content is instructed from the base station apparatus to the mobile station apparatus as data allocation information.

  Since the reference signal may have a frequency band that overlaps with a reference signal assigned to another user who is another wireless communication apparatus using the same wireless communication system, the reference signal can be code-multiplexed with the reference signal of the other user. In addition, the sequence parameters used for the reference signal have a one-to-one correspondence with the frequency hopping pattern at the time of frequency hopping, which is an example of the frequency domain arrangement information. For example, when a CAZAC sequence is used for the reference signal, the root index and cyclic shift amount of the sequence are determined according to the frequency hopping pattern. That is, the reference signal is uniquely determined by the frequency hopping pattern.

(1) Hopping flag
Of the frequency hopping, changing the mapping of the resource block RB in slot units within 1 TTI as in the example of the frame format in FIG. 1 is referred to as Intra-TTI hopping. Although not shown here, for example, the next TTI may be mapped to a different resource block RB, and changing the mapping of the resource block RB for each TTI over a plurality of TTIs in this way is called Inter-TTI hopping. Call. In the present embodiment, the hopping flag (Hopping flag) is used as hopping availability information indicating whether or not Intra-TTI hopping is applied, and the base station apparatus instructs the mobile station apparatus.

  FIG. 2 is a diagram illustrating an example of a hopping flag. The hopping flag is composed of, for example, 1 bit, and “Intra-TTI hopping” or “Intra-TTI hopping” is assigned to each value “0” and “1”, respectively. In the frame format of FIG. 1, since Intra-TTI hopping is applied, the hopping flag is “1”.

(2) Resource Block RB Allocation Information FIG. 3 is a diagram illustrating an example of RB allocation information in the first embodiment. The RB allocation information includes the frequency domain arrangement information, and is composed of, for example, 9 bits. Corresponding to each value, the start position (RB start position) of the resource block RB of the first slot, the transmission of the mobile station apparatus Information indicating the number of resource blocks RB (number of RBs) allocated to, and the cyclic shift amount m of the reference signal when code-multiplexing with reference signals of other users is allocated. In this embodiment, since the reference signal is also arranged in the resource block RB in which the data symbol is mapped in the adjacent slot, the reference signal of both is code-multiplexed and transmitted in consideration of the overlap with the reference signal of another user.

  Although the number of bits of the RB allocation information varies depending on the number of all resource blocks RB, it is 25 in the frame format of FIG. The contents of the RB allocation information are as shown in FIG. In this case, since the RB start position of the first slot is RB # 24 and the number of RBs is 2, when the cyclic shift amount is m = 1, the RB allocation information is “000110001”. The amount of cyclic shift will be described in detail later. The RB start position of the second slot is based on the hopping flag (1) above. That is, when Intra-TTI hopping is not performed, the position is the same as the RB start position of the first slot. When Intra-TTI hopping is performed, it is determined by a predetermined hopping pattern with reference to the RB start position of the first slot. For example, if the hopping pattern is a target arrangement centered on RB # 13 which is the central resource block RB, the RB start position of the second slot corresponding to the first slot of FIG. 1 is RB # 1.

  Next, the configuration and operation of the wireless communication apparatus according to the first embodiment will be described. First, a transmitter in the mobile station apparatus will be described. FIG. 4 is a block diagram showing a configuration of a transmission unit of the mobile station apparatus according to the first embodiment.

  The transmission unit of the mobile station apparatus includes a transmission data input unit 11, an error correction coding unit 12, a primary modulation unit 13, a DFT unit 14, a control channel reception unit 15, an FH information extraction unit 16, a reference signal determination unit 17, and a reference signal. The generator 18 includes a time / frequency domain mapping unit 19, an IFFT unit 20, a CP adding unit 21, a time windowing unit 22, an RF unit 23, and an antenna 24.

  Here, the control channel receiving unit 15 realizes the function of the control channel receiving unit that receives the control channel notified from the base station apparatus. The reference signal determination unit 17 realizes the function of the reference signal determination unit that determines the arrangement of the reference signals based on the data allocation information included in the control channel. The reference signal generation unit 18 realizes the function of the reference signal generation unit that generates a reference signal according to the determined arrangement. Further, the time / frequency domain mapping unit 19, the RF unit 23, and the like realize the function of a transmission unit that generates a transmission signal including a reference signal in accordance with the data allocation information and transmits it to the base station apparatus.

  First, transmission data input by the transmission data input unit 11 is error correction encoded by the error correction encoding unit 12. Then, after performing primary modulation processing such as QPSK in the primary modulation unit 13, the DFT unit 14 converts the time domain modulation signal into the frequency domain by discrete Fourier transform (DFT), and the time / frequency domain mapping unit 19. To enter.

  In parallel with this, the control channel receiving unit 15 receives a downlink control channel from the base station apparatus via a reception RF unit (not shown). The downlink control channel is also called Physical Downlink Control Channel (PDCCH). Then, the FH information extraction unit 16 extracts frequency hopping information (FH information) related to frequency mapping from the downlink control channel and inputs it to the time / frequency domain mapping unit 19. This FH information includes RB allocation information as the above-described data allocation information, and includes information indicating a frequency hopping pattern as frequency domain arrangement information.

  At the same time, the reference signal determining unit 17 determines the sequence length and content of the reference signal (DMRS) from the FH information, and the reference signal generating unit 18 represents a data sequence representing the reference signal based on the following generation formula: Is generated and then input to the time / frequency domain mapping unit 19.

Here, a method of generating a DMRS sequence in the reference signal determination unit 17 and the reference signal generation unit 18 will be described by taking as an example a case where the reference signal (DMRS) is a CAZAC sequence. First, a q-order Zadoff-Chu sequence x _q (m) is obtained by the following equation (1).

In the example of the frame format in FIG. 1, the number of used RBs is 2. In the LTE uplink, since the number of subcarriers per RB is defined as 12, the DMRS sequence length is M ^RS _SC = 12 × 2 = 24. Therefore, N ^RS _ZC is 23 which is the maximum prime number close to 24.

Then, based on x _q (m) obtained above, base sequence for DMRS r ^- generating _u, v (n) is defined by equation 2 below.

Then, DMRS reference sequence r ^- give _u, v phase shift as shown in Expression 3 below with respect to (n).

Finally, a DMRS sequence r ^PUSCH (•) to be actually mapped is obtained from the DMRS reference sequence r ^(α) _{u, v} (n) given the phase shift as shown in the following equation (4).

  In Equation 4, m and n are as shown in Equation 5 below.

  Furthermore, in order to code-multiplex with the reference signal of another user, the cyclic shift amount of the reference signal is determined based on the RB start position and the RB number information in the FH information. For example, in the example of the frame format in FIG. 1, since the frequency band overlaps with the hopping pattern (000011001) shown in FIG. 5, it is necessary to make the reference signals of both orthogonal.

  Therefore, different cyclic shifts are given to both reference signals. Various methods can be considered for giving the cyclic shift. For example, a method of changing m in Equation 4 according to the hopping pattern is conceivable. As an example, when the RB start positions of the first slot and the second slot are P1 and P2, respectively, and m is defined as shown in the following Equation 6, the cyclic shift amount is as shown in FIG.

  Based on FIG. 3, the reference signal determining unit 17 determines the sequence length and the content of the reference signal from the FH information, and the reference signal generating unit 18 generates a DMRS sequence.

  Next, the time / frequency domain mapping unit 19 performs data symbol and reference signal mapping on the two-dimensional table shown in FIG. 1 based on the number of RBs and the mapping pattern specified from the FH information. At this time, the reference signals are arranged in a total of four locations, that is, resource blocks RB in which data symbols are mapped in the own slots and resource blocks RB in which data symbols are mapped in adjacent slots.

  Thereafter, the IFFT unit 20 converts the transmission symbols into time domain signals by fast inverse Fourier transform (IFFT) for each transmission symbol LB. Then, a CP (Cyclic Prefix) is added by the CP adding unit 21, a time windowing process is performed by the time windowing unit 22, a baseband signal is converted into a high frequency signal by the RF unit 23, and then the high frequency signal is transmitted. The signal is transmitted from the antenna 24 to the base station apparatus of the communication partner station.

  Note that the DMRS sequence of the reference signal described above is an example, and the present invention is not limited to this method. It suffices if reference signals that need to be code-multiplexed are orthogonal to each other or a sequence with low cross-correlation can be generated. For example, instead of changing the cyclic shift amount m in Equation 4, a method of changing any one (or more) of the order q in Equation 1, the fixed offset θ in Equation 2, and the phase shift amount α in Equation 3 is also conceivable. .

  Alternatively, in the mapping example of the frame format in FIG. 1, the DMRS sequence length is doubled to 48 and is divided and arranged in the same transmission symbol LB (for example, in resource blocks RB # 1 to # 2 and RB # 24 to # 25) A separate arrangement) is also conceivable. In this case, since a longer sequence length can be secured, higher orthogonality can be expected. Also, as long as the sequence set maintains the orthogonality of reference signals between users, the DMRS sequence arranged in transmission symbols LB # 4 and LB # 11 may be changed.

  Then, the receiver in a base station apparatus is demonstrated. FIG. 6 is a block diagram illustrating a configuration of the receiving unit of the base station apparatus according to the first embodiment.

  The reception unit of the base station apparatus includes an antenna 31, an RF unit 32, an FFT unit 33, a channel separation unit 34, a channel estimation unit 35, a buffer unit 36, a 0 / primary interpolation unit 37, a frequency domain equalization unit 38, and an IDFT unit. 39, an error correction decoding unit 40, a received data extraction unit 41, an uplink quality measurement unit 42, an FH information determination unit 43, and a control channel transmission unit 44.

  Here, the RF unit 32 and the like realize the function of a receiving unit that receives a signal transmitted from the mobile station apparatus. The channel separation unit 34 realizes the function of a reference signal extraction unit that extracts a reference signal from the received reception signal. The channel estimator 35 implements the function of a channel estimator that performs channel estimation of the transmission path using the reference signal. The 0 / primary interpolation unit 37 implements a function of an interpolation unit that interpolates channel estimation values obtained by channel estimation in a plurality of transmission slots. The uplink quality measurement unit 42 implements the function of an uplink quality measurement unit that measures the quality of the uplink from the mobile station apparatus to the base station apparatus based on the received signal. The FH information determination unit 43 determines data allocation related to frequency hopping in which at least two transmission slots among a plurality of transmission slots continuously arranged in time are arranged in different frequency regions based on uplink quality. The function of the data allocation determination unit is realized. The control channel transmission unit 44 realizes the function of a control channel transmission unit that generates a control channel including the determined data allocation information and transmits the control channel to the mobile station apparatus.

  First, the received signal of the high frequency signal received from the antenna 31 is converted into a baseband signal by the RF unit 32, and then the time domain signal is converted into a frequency domain signal by fast Fourier transform (FFT) at the FFT unit 33. Next, the channel separation unit 34 classifies the received signal into three types: data symbol, reference signal, and uplink quality measurement channel. Here, the data symbol is also called Physical Uplink Shared Channel (PUSCH), and the uplink quality measurement channel is also called Sounding RS.

  Among these signals, data symbols are directly input to the frequency domain equalization unit 38. For the reference signal, the channel estimation unit 35 obtains a channel estimation value by performing a correlation operation with a reference signal prepared in advance on the receiving side, and stores the channel estimation value in the buffer 36. The 0 / primary interpolation unit 37 performs zero-order interpolation processing within a slot or TTI, or primary interpolation processing within TTI, and then inputs the result to the frequency domain equalization unit 38. These 0/1 linear interpolations operate exclusively. For example, the moving speed of the mobile station is detected by measuring a frequency offset (Doppler frequency) in the previous stage of the channel estimation unit 35, and the zero order interpolation and the primary interpolation are performed. Interpolation may be switched dynamically.

  Then, the frequency domain equalization unit 38 performs data symbol correction processing based on the amplitude / phase variation information obtained from the channel estimation value. Thereafter, the IDFT unit 39 converts the signal into a time domain signal by discrete inverse Fourier transform (IDFT), the error correction decoding unit 40 performs error correction coding processing, and the received data extraction unit 41 performs a desired received data sequence. Get.

  For the uplink quality measurement channel, the uplink quality measurement unit 42 measures the reception quality (SNR, etc.) for each resource block RB, and then the FH information determination unit 43 determines the FH information based on the reception quality. decide. Then, the control channel transmission unit 44 generates and modulates the downlink control channel, and transmits and notifies the downlink control channel including the FH information to the mobile station apparatus of the communication partner station.

  Next, the operation of the wireless communication apparatus according to the first embodiment will be described along the procedure. FIG. 7 is a flowchart showing a processing procedure of the wireless communication apparatus according to the first embodiment. (A) shows a process of the receiving unit of the base station apparatus, and (b) shows a process of the transmitting unit of the mobile station apparatus. It is a thing.

  In the base station apparatus, the RF unit 32, the FFT unit 33, and the channel separation unit 34 first receive and process uplink signals from the mobile station apparatus, and extract an uplink quality measurement channel (Sounding RS) (step S11). The uplink quality measurement unit 42 measures the reception quality for each frequency domain based on the uplink quality measurement channel (step S12), and the FH information determination unit 43 determines the RB start position, RB based on the reception quality. FH information including the number, mapping pattern, etc. is determined (step S13). Thereafter, the control channel transmission unit 44 generates a downlink control channel (PDCCH) including the determined FH information and transmits it to the mobile station apparatus (step S14).

  On the other hand, in the mobile station apparatus, first, the control channel receiving unit 15 receives the downlink control channel from the base station apparatus (step S21), and the FH information extracting unit 16 selects the hopping pattern (FH pattern) from the downlink control channels. FH information such as) is extracted (step S22). Then, the reference signal determining unit 17 and the reference signal generating unit 18 determine the DMRS sequence and the cyclic shift amount of the reference signal, and generate a reference signal (step S23). Thereafter, the time / frequency domain mapping unit 19 performs time domain and frequency domain mapping for the data symbol (PUSCH) and the reference signal (DMRS) as described above, and the generated uplink signal is converted into an IFFT unit 20 and a CP adding unit. 21, the time windowing unit 22 and the RF unit 23 transmit to the base station apparatus (step S24).

  FIG. 8 is a diagram showing a communication format of a comparative example. The frame format of this comparative example is obtained by mapping the reference signal only in the same band (same resource block) as the data symbol in the same slot. That is, data symbols and reference signals are mapped to RB # 24 and # 25 in the first slot and RB # 1 and # 2 in the second slot, respectively. In the comparative example of FIG. 8, since only one reference signal is arranged in the same resource block RB in 1 TTI, noise suppression by zero-order interpolation and phase rotation correction by primary interpolation cannot be performed, and highly accurate channel estimation is performed. I can't.

  On the other hand, in the first embodiment, since two reference signals are arranged in the same resource block RB within 1 TTI, 0th-order interpolation within TTI (that is, averaging processing of two channel estimation values), Or it is the structure which can perform primary interpolation (namely, linear interpolation process of two channel estimated values). With this configuration, higher channel estimation accuracy can be expected. Therefore, even in a communication format in which the arrangement of reference signals is limited, by allowing a plurality of reference signals to be arranged on the time axis, noise can be suppressed by zero-order interpolation in a low SNR environment, and primary in a high-speed moving environment. Interpolation can improve followability to fading fluctuations, so that reception performance can be improved.

(Second Embodiment)
FIG. 9 is a diagram showing a communication format of the wireless communication system according to the second embodiment of the present invention. The second embodiment is a partial modification of the first embodiment described above, and here, a description will be given centering on parts different from the first embodiment.

  In the second embodiment, reference signals are mapped to all resource blocks RB # 1 to # 25 in transmission symbols LB # 4 and # 11 in which reference signals can be arranged. Thereby, the reception performance is improved. Even in such a frame format configuration, two reference signals are mapped onto the same resource block RB within 1 TTI, as in the first embodiment. However, in this case, unlike the first embodiment, since the reference signal overlaps regardless of the hopping pattern of other users, it is necessary to be orthogonal to the reference signals of all hopping patterns.

  There are various means for orthogonalizing the reference signal. For example, in the above-described mathematical formula for generating the DMRS sequence, a method of changing the fixed offset θ in Equation 2 and the order q in Equation 1 according to the hopping pattern is considered. It is done. Here, the possible range of θ is as shown in Equation 2 to Equation 7 below.

In the second embodiment, since all resource blocks RB are used as reference signals, the sequence length of the reference signal DMRS is uniformly 25 × 12 = 300 regardless of the frequency hopping pattern. Therefore, N ^RS _ZC in Equation 7 is 293 which is the prime number closest to the DMRS sequence length 300.

  Taking the above factors into consideration, the reference signal is cyclic shifted, and the reference signals of all hopping patterns are multiplexed. FIG. 10 is a diagram illustrating an example of RB allocation information according to the second embodiment. Using this RB allocation information, the cyclic shift amount of the reference signal is determined, and a DMRS sequence is generated.

  Here, the RB allocation information is composed of, for example, 9 bits, corresponding to each value, the start position (RB start position) of the resource block RB in the first slot, and the resource block RB allocated for transmission of the mobile station apparatus. The number (number of RBs) and information indicating the cyclic shift amounts θ and q of the reference signal when code-multiplexing with reference signals of other users are assigned. In the example of FIG. 10, θ is preferentially changed, and q is changed when it reaches 292, which is the maximum value that θ can take. Although sequences with different q are not strictly orthogonal, in this example, the sequence length is as long as 300, so the cross-correlation is suppressed to a negligible level.

  Further, in the second embodiment, since the reference signal is mapped to the entire frequency band, a secondary effect that the reception quality of all resource blocks RB can be measured without using the uplink quality measurement channel. You can also get

  FIG. 11 is a block diagram showing the configuration of the transmission unit of the mobile station apparatus according to the second embodiment, and FIG. 12 is a block diagram showing the configuration of the reception unit of the base station apparatus according to the second embodiment. Here, only different parts from the first embodiment will be described.

  The transmission unit of the mobile station apparatus is almost the same as that of the first embodiment shown in FIG. 4, but some of the functions of the reference signal determination unit 51, the reference signal generation unit 52, and the time / frequency domain mapping unit 53 are. Is different. The reference signal determination unit 51 determines the content of the reference signal DMRS based on the RB allocation information of FIG. Then, the DMRS sequence is generated by the reference signal generation unit 52 using the above-described mathematical formula. The time / frequency domain mapping unit 53 arranges reference signals in all resource blocks RB when arranging data symbols and reference signals.

  The receiving unit of the base station apparatus is partially different from the first embodiment shown in FIG. 6, and the uplink quality measuring unit 62, the FH information determining unit 63, and the control channel transmitting unit 64 are the 0 / primary interpolation unit 37. The reception quality of the uplink is measured using reference signals of all resource blocks RB without using the uplink quality measurement channel. At this time, the channel separation unit 61 classifies the received signal into a data symbol and a reference signal. Uplink quality measuring section 62 measures the reception quality (SNR, etc.) for each resource block RB using the reference signal, and FH information determining section 63 determines the FH information based on the received quality. Then, the control channel transmission unit 64 generates and modulates the downlink control channel, and transmits and notifies the downlink control channel including the FH information to the mobile station apparatus of the communication counterpart station.

  Next, the operation of the wireless communication apparatus according to the second embodiment will be described along the procedure. FIG. 13 is a flowchart illustrating a processing procedure of the wireless communication apparatus according to the second embodiment. (A) illustrates a process of the receiving unit of the base station apparatus, and (b) illustrates a process of the transmitting unit of the mobile station apparatus. It is a thing.

  In the base station apparatus, first, the RF unit 32, the FFT unit 33, and the channel separation unit 61 receive and process the uplink signal from the mobile station apparatus, and extract the reference signal (DMRS) (step S31). At this time, the channel estimation unit 35, the buffer unit 36, and the 0 / primary interpolation unit 37 perform channel estimation and 0 / primary interpolation using the reference signal. Then, the uplink quality measurement unit 62 measures the reception quality for each frequency domain based on the reference signal (step S32), and the FH information determination unit 63 determines the RB start position, the number of RBs, FH information including a mapping pattern is determined (step S33). Thereafter, the control channel transmission unit 64 generates a downlink control channel (PDCCH) including the determined FH information and transmits it to the mobile station apparatus (step S34).

  On the other hand, in the mobile station apparatus, first, the control channel receiving unit 15 receives the downlink control channel from the base station apparatus (step S41), and the FH information extracting unit 16 selects the hopping pattern (FH pattern) from the downlink control channels. FH information such as) is extracted (step S42). Then, the reference signal determining unit 51 and the reference signal generating unit 52 determine the DMRS sequence and the cyclic shift amount of the reference signal, and generate the reference signal (step S43). After that, the time / frequency domain mapping unit 53 performs time domain and frequency domain mapping on the data symbol (PUSCH) and the reference signal (DMRS) as described above, and the generated uplink signal is converted into an IFFT unit 20 and a CP adding unit. 21, the time windowing unit 22 and the RF unit 23 transmit the data to the base station apparatus (step S44).

  As described above, in the second embodiment, by arranging the reference signals in all the resource blocks, two reference signals are mapped on the same resource block RB in 1 TTI as in the first embodiment. Therefore, the zero-order interpolation and the first-order interpolation can be performed based on the channel estimation values obtained from both, and a highly accurate channel estimation value can be obtained. Therefore, it is possible to improve reception performance in a low SNR environment or a high-speed moving environment. Also, by using the reference signals arranged in all resource blocks, it is possible to measure the reception quality in all frequency regions without using the uplink quality measurement channel.

(Third embodiment)
The third embodiment is an example in which whether or not frequency hopping is possible is determined based on cell environment information held in advance by the base station apparatus, and application of frequency hopping in an uplink signal from the mobile station apparatus to the base station apparatus is switched.

  As described above, in the fast fading environment, if two or more reference signals are not arranged in the same resource block RB within 1 TTI, the channel estimation unit on the receiver side (base station apparatus) may perform fast fading. Tracking cannot be performed, and the error rate characteristics are greatly deteriorated. Therefore, without performing Intra-TTI hopping as shown in the frame format examples of the embodiments of FIG. 1 and FIG. 9, channel estimation values obtained from the reference signals of the first and second slots are linearly interpolated, A configuration that follows fast fading is more desirable.

  On the other hand, in a low-speed fading environment, the embodiment shown in FIGS. 1 and 9 can be used even in a configuration in which one reference signal is arranged in the same resource block RB within 1 TTI as shown in the comparative example of FIG. Even in a configuration in which two or more reference signals are arranged in the same resource block RB, a large performance difference does not appear. In this case, the noise suppression effect can be obtained by averaging the channel estimation values obtained from the two resource blocks RB with the configuration as in the first or second embodiment. The effect can be confirmed only in the worst environment where the SNR is low such that the device exists at the cell edge, and there is no improvement effect in the high SNR environment where the mobile station device exists near the base station device. . Therefore, a configuration in which intra-TTI hopping is performed in a low-speed fading environment to reduce the influence of frequency selective fading is more desirable.

  In view of the above, in the third embodiment, as the cell environment information, the base station apparatus has a cell setting flag (Configuration flag) indicating whether the base station apparatus is a High Speed Cell or a Normal Cell in advance, and the cell setting flag The applicability of Intra-TTI hopping is determined according to the contents of. Here, High Speed Cell indicates that there is a possibility that the base station apparatus in the cell includes a mobile station apparatus with high-speed movement in coverage. For example, there is a base station apparatus laid along the Shinkansen line. On the other hand, Normal Cell indicates that there is no possibility that the base station apparatus includes a mobile station apparatus with high-speed movement in the cell. For example, there is a base station device laid in an underground mall.

  FIG. 14 is a diagram illustrating an example of a cell setting flag. The cell setting flag is composed of, for example, 1 bit, and “Normal Cell” or “High Speed Cell” is assigned to each value “0” and “1”. Whether or not Intra-TTI hopping can be applied is determined according to the cell setting flag. For example, in Normal Cell, the cell setting flag is “0”. In this case, Intra-TTI hopping is applied (the hopping flag as hopping availability information is set to “1”). In the High Speed Cell, the cell setting flag is “1”. In this case, Intra-TTI hopping is not applied (the hopping flag is set to “0”).

  FIG. 15 is a block diagram illustrating a configuration of the receiving unit of the base station apparatus according to the third embodiment. Here, only different parts from the first embodiment will be described. The configuration and operation of the transmission unit of the mobile station apparatus in the third embodiment are the same as those in the first embodiment shown in FIG. In the third embodiment, the reference signal may not be arranged as in the first and second embodiments, and only one reference signal may be arranged in the same resource block RB within 1 TTI. .

  The receiving unit of the base station apparatus is substantially the same as that of the first embodiment shown in FIG. 6, but a part of the function of the FH information determining unit 71 is different. The FH information determination unit 71 reads a cell setting flag when determining FH information including RB allocation information as data allocation information based on the reception quality for each frequency domain measured by the uplink quality measurement unit 42. It has a function. Here, the FH information determination unit 71, based on cell environment information held in advance, in one transmission unit with a predetermined number of transmission slots continuously arranged in time, at least two transmission slots in this transmission unit A function of a hopping availability determination unit that determines whether to apply Intra-TTI hopping that is arranged in different frequency regions is realized.

  When the cell setting flag is “0”, the FH information determination unit 71 determines that the cell is a normal cell, and it is more preferable to apply Intra-TTI hopping. Therefore, the hopping flag in the FH information is set. Set to “1”. At the same time, the number of RBs and the frequency hopping pattern are determined based on the reception quality for each resource block RB obtained from the uplink quality measurement unit 42. Then, in the control channel transmission unit 44, a downlink control channel including these FH information is generated, transmitted to the mobile station apparatus, and instructed.

  When the cell setting flag is “1”, the FH information determination unit 71 determines that the cell is a high speed cell, and it is more preferable not to apply Intra-TTI hopping. Set the hopping flag to “0”. At the same time, the number of RBs and the RB arrangement position are determined based on the reception quality and the like for each resource block RB obtained from the uplink quality measurement unit 42. Then, in the control channel transmission unit 44, a downlink control channel including these FH information is generated, transmitted to the mobile station apparatus, and instructed.

  In the third embodiment, the Inter-TTI hopping is not particularly limited. The arrangement of resource blocks RB for each TTI is determined each time based on the uplink quality measurement result on the base station side.

  Next, the operation of the wireless communication apparatus according to the third embodiment will be described along a procedure. FIG. 16 is a flowchart illustrating a processing procedure of the wireless communication device according to the third embodiment, where (a) illustrates processing of the receiving unit of the base station device, and (b) illustrates processing of the transmitting unit of the mobile station device. It is a thing.

  In the base station apparatus, the RF unit 32, the FFT unit 33, and the channel separation unit 34 first receive and process the uplink signal from the mobile station apparatus, and extract the uplink quality measurement channel (Sounding RS) (step S51). Then, the uplink quality measuring unit 42 measures the reception quality for each frequency domain based on the uplink quality measurement channel (step S52). Subsequently, the cell setting flag is read by the FH information determination unit 71 to determine whether or not Intra-TTI hopping can be applied (step S53), and the number of RBs and frequency hopping pattern (when Inter-TTI hopping is performed) based on reception quality. Alternatively, FH information including the RB arrangement position (when Inter-TTI hopping is not performed) is determined (step S54). Thereafter, the control channel transmission unit 44 generates a downlink control channel (PDCCH) including the determined FH information and transmits it to the mobile station apparatus (step S55).

  On the other hand, in the mobile station apparatus, first, the control channel receiving unit 15 receives the downlink control channel from the base station apparatus (step S61), and the FH information extracting unit 16 extracts the FH information from the downlink control channel ( Step S62). Then, the reference signal determining unit 17 and the reference signal generating unit 18 determine the DMRS sequence of the reference signal, and generate a reference signal (step S63). Thereafter, the time / frequency domain mapping unit 19 performs time domain and frequency domain mapping on the data symbol (PUSCH) and the reference signal (DMRS), and the generated uplink signal is converted into an IFFT unit 20, a CP adding unit 21, a time windowing It transmits to a base station apparatus in the part 22 and RF part 23 (step S64).

  As described above, in the third embodiment, based on information indicating whether the cell held by the base station apparatus is a high speed cell or a normal cell, whether or not intra-TTI hopping is applicable is determined and frequency hopping operation is switched. By setting, it is possible to execute a desired frequency hopping operation in each of the high-speed moving environment and the low-speed moving environment, and obtain appropriate performance according to the cell environment. Therefore, reception performance in a high-speed moving environment can be improved.

  In the above embodiment, the case where the cell setting flag is notified by the downlink control channel (PDCCH) has been described as an example. However, as a notification means, the base station apparatus periodically notifies the mobile station apparatus. It is also conceivable to use a broadcast channel (BCH).

  It should be noted that the present invention is not limited to those shown in the above-described embodiments, and those skilled in the art can also make changes and applications based on the description in the specification and well-known techniques. Yes, included in the scope of protection. Various modifications can be made to the configuration of communication slots in the frame format, the arrangement of data symbols, the arrangement of reference signals corresponding to the data symbols, the pattern of frequency hopping, and the like.

  The present invention has an effect of enabling high-accuracy channel estimation even in a communication format in which the arrangement of reference signals is restricted, and improving reception performance in a low SNR environment or a high-speed moving environment. It is useful as a mobile station apparatus and a base station apparatus used for body communication and a wireless communication system.

The figure which shows the communication format of the radio | wireless communications system which concerns on the 1st Embodiment of this invention. The figure which shows an example of a hopping flag The figure which shows an example of RB allocation information in 1st Embodiment The block diagram which shows the structure of the transmission part of the mobile station apparatus which concerns on 1st Embodiment. The figure which shows the other hopping pattern in the communication format of 1st Embodiment. The block diagram which shows the structure of the receiving part of the base station apparatus which concerns on 1st Embodiment. The flowchart which shows the process sequence of the radio | wireless communication apparatus in 1st Embodiment. The figure which shows the frame format of the comparative example The figure which shows the communication format of the radio | wireless communications system which concerns on the 2nd Embodiment of this invention. The figure which shows an example of RB allocation information in 2nd Embodiment The block diagram which shows the structure of the transmission part of the mobile station apparatus which concerns on 2nd Embodiment. The block diagram which shows the structure of the receiving part of the base station apparatus which concerns on 2nd Embodiment. 7 is a flowchart showing a processing procedure of the wireless communication apparatus according to the second embodiment. The figure which shows an example of the cell setting flag in 3rd Embodiment The block diagram which shows the structure of the receiving part of the base station apparatus which concerns on 3rd Embodiment. 9 is a flowchart showing a processing procedure of a wireless communication apparatus according to the third embodiment. Diagram showing the frame format assumed in the prior art Block diagram of channel estimation / equalization processing unit in a prior art receiver

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Transmission data input part 12 Error correction encoding part 13 Primary modulation part 14 DFT part 15 Control channel receiving part 16 FH information extraction part 17, 51 Reference signal determination part 18, 52 Reference signal generation part 19, 53 Time / frequency domain mapping Section 20 IFFT section 21 CP addition section 22 Time Windowing section 23, 32 RF section 24, 31 Antenna 33 FFT section 34, 61 Channel separation section 35 Channel estimation section 36 Buffer section 37 0 / primary interpolation section 38 Frequency domain equalization section 38 39 IDFT unit 40 Error correction decoding unit 41 Received data extraction unit 42, 62 Uplink quality measurement unit 43, 63, 71 FH information determination unit 44, 64 Control channel transmission unit

Claims (12)

In the first transmission slot and the second transmission slot that are continuously arranged in time, the data symbol of the first transmission slot and the data symbol of the second transmission slot can be arranged in different frequency regions. A mobile station apparatus of a wireless communication system using a communication format,
A control channel receiving unit for receiving a control channel notified from the base station device;
A reference signal determining unit that determines the arrangement of reference signals based on data allocation information included in the control channel;
A reference signal generator for generating the reference signal according to the determined arrangement;
A transmission unit that generates the transmission signal including the reference signal according to the data allocation information, and transmits the transmission signal to the base station device,
The data allocation information defines data allocation related to frequency hopping in which data symbols of the first transmission slot and data symbols of the second transmission slot are arranged in different frequency regions,
In the first transmission slot, the reference signal determination unit refers to the frequency domain in which the data symbol of the first transmission slot is arranged and the frequency domain in which the data symbol of the second transmission slot is arranged. In the second transmission slot, the reference signal is arranged in a frequency domain in which data symbols in the second transmission slot are arranged and in a frequency domain in which data symbols in the first transmission slot are arranged. Mobile station device to be arranged. The mobile station apparatus according to claim 1,
The reference signal generation unit is a mobile station apparatus that generates the reference signal so as to be code-multiplexable with another wireless communication apparatus using the same wireless communication system. The mobile station apparatus according to claim 1,
The reference signal generation unit is a mobile station apparatus in which the content of the reference signal is uniquely determined by frequency domain arrangement information in the data allocation information. The mobile station apparatus according to claim 1,
The reference signal determination unit may include the reference in all frequency regions in which data in the first transmission slot can be arranged and in all frequency regions in which data in the second transmission slot can be arranged. A mobile station apparatus that arranges signals. In the first transmission slot and the second transmission slot that are continuously arranged in time, the data symbol of the first transmission slot and the data symbol of the second transmission slot can be arranged in different frequency regions. A base station apparatus of a wireless communication system using a communication format,
A receiver for receiving a signal transmitted from the mobile station device;
A reference signal extraction unit that extracts a reference signal from the received reception signal;
A channel estimation unit for performing channel estimation of a transmission path using the reference signal;
An interpolation unit for interpolating the channel estimation value by the channel estimation in a plurality of transmission slots,
In the first transmission slot, the interpolation unit transmits the reference signal in a frequency domain in which a data symbol in the first transmission slot is arranged and a frequency domain in which a data symbol in the second transmission slot is arranged. In the second transmission slot, the reference signal is placed in a frequency domain in which data symbols in the second transmission slot are arranged and in a frequency domain in which data symbols in the first transmission slot are arranged. A base station apparatus that performs zero-order interpolation or first-order interpolation on channel estimation values of reference signals in the same frequency region in the first transmission slot and the second transmission slot when arranged. The base station apparatus according to claim 5, wherein
Reference signals in the same frequency region in the first transmission slot and the second transmission slot are code-multiplexed between different wireless communication devices using the same wireless communication system,
The channel estimation unit is a base station apparatus that obtains a channel estimation value of a reference signal of the first transmission slot code-multiplexed and a channel estimation value of a reference signal of the second transmission slot code-multiplexed. The base station apparatus according to claim 5, wherein
An uplink quality measuring unit that measures the quality of the uplink from the mobile station device to the base station device by the received signal;
A data allocation determining unit that determines data allocation related to frequency hopping in which the data symbols of the first transmission slot and the data symbols of the second transmission slot are arranged in different frequency regions based on the uplink quality;
A base station apparatus further comprising: a control channel transmission unit that generates a control channel having the determined data allocation information and transmits the control channel to the mobile station apparatus. The base station apparatus according to claim 7,
The uplink quality measurement unit may include the frequency region in which data in the first transmission slot can be arranged and the frequency region in which data in the second transmission slot can be arranged. A base station apparatus that measures uplink quality using reference signals in all frequency regions of the received signal when a reference signal is arranged. In the first transmission slot and the second transmission slot that are continuously arranged in time, the data symbol of the first transmission slot and the data symbol of the second transmission slot can be arranged in different frequency regions. A mobile station apparatus of a wireless communication system using a communication format,
A control channel receiving unit for receiving a control channel notified from the base station device;
A transmission unit that generates a transmission signal including a data symbol and a reference signal according to data allocation information included in the control channel, and transmits the transmission signal to the base station apparatus,
The data allocation information includes, in one transmission unit with a predetermined number of transmission slots including the first transmission slot and the second transmission slot, the data symbol of the first transmission slot and the first transmission slot in the transmission unit. Hopping availability information indicating whether or not intra-TTI hopping can be applied to arrange data symbols of two transmission slots in different frequency regions,
The transmission unit is a mobile station apparatus that arranges data symbols and reference signals in a frequency domain according to the hopping availability information. In the first transmission slot and the second transmission slot that are continuously arranged in time, the data symbol of the first transmission slot and the data symbol of the second transmission slot can be arranged in different frequency regions. A base station apparatus of a wireless communication system using a communication format,
A receiver for receiving a signal transmitted from the mobile station device;
Based on cell environment information held in advance, in one transmission unit with a predetermined number of transmission slots including the first transmission slot and the second transmission slot, data symbols of the first transmission slot within the transmission unit And a hopping availability determination unit that determines whether to apply Intra-TTI hopping, in which data symbols of the second transmission slot are arranged in different frequency regions,
Generating a control channel having data allocation information including hopping availability information instructing applicability of the Intra-TTI hopping, and transmitting the control channel to the mobile station apparatus;
A base station apparatus comprising: In the first transmission slot and the second transmission slot that are continuously arranged in time, the data symbol of the first transmission slot and the data symbol of the second transmission slot can be arranged in different frequency regions. A wireless communication system using a communication format,
A control channel receiving unit for receiving a control channel notified from the base station device;
A reference signal determining unit that determines the arrangement of reference signals based on data allocation information included in the control channel;
A reference signal generator for generating the reference signal according to the determined arrangement;
A transmission unit that generates the transmission signal including the reference signal according to the data allocation information, and transmits the transmission signal to the base station device,
The data allocation information defines data allocation related to frequency hopping in which data symbols of the first transmission slot and data symbols of the second transmission slot are arranged in different frequency regions,
In the first transmission slot, the reference signal determination unit refers to the frequency domain in which the data symbol of the first transmission slot is arranged and the frequency domain in which the data symbol of the second transmission slot is arranged. In the second transmission slot, the reference signal is arranged in a frequency domain in which data symbols in the second transmission slot are arranged and in a frequency domain in which data symbols in the first transmission slot are arranged. A mobile station device to be arranged;
A receiving unit for receiving a signal transmitted from the mobile station device;
A reference signal extraction unit that extracts a reference signal from the received reception signal;
A channel estimation unit for performing channel estimation of a transmission path using the reference signal;
An interpolation unit for interpolating the channel estimation value by the channel estimation in a plurality of transmission slots,
The interpolating unit performs a zero-order interpolation or a first-order interpolation on a channel estimation value of a reference signal in the same frequency region arranged in the first transmission slot and the second transmission slot; and
A wireless communication system. In the first transmission slot and the second transmission slot that are continuously arranged in time, the data symbol of the first transmission slot and the data symbol of the second transmission slot can be arranged in different frequency regions. A wireless communication system using a communication format,
A control channel receiving unit for receiving a control channel notified from the base station device;
A transmission unit that generates a transmission signal including a data symbol and a reference signal according to data allocation information included in the control channel, and transmits the transmission signal to the base station apparatus,
The data allocation information includes, in one transmission unit with a predetermined number of transmission slots including the first transmission slot and the second transmission slot, the data symbol of the first transmission slot and the first transmission slot in the transmission unit. Hopping availability information indicating whether or not intra-TTI hopping can be applied to arrange data symbols of two transmission slots in different frequency regions,
The transmitter is configured to arrange a data symbol and a reference signal in a frequency domain according to the hopping availability information; and
A receiving unit for receiving a signal transmitted from the mobile station device;
A hopping availability determination unit that determines whether to apply the Intra-TTI hopping based on cell environment information held in advance,
A base station apparatus comprising: a control channel transmission unit that generates a control channel having data allocation information including hopping availability information that instructs whether to apply the Intra-TTI hopping, and transmits the information to the mobile station apparatus;
A wireless communication system.