JP4713553B2 - Wireless terminal apparatus and wireless base station apparatus - Google Patents

Description

  The present invention relates to a radio terminal apparatus and a radio base station apparatus of a radio system such as an Evolved UTRA (E-UTRA) system.

In recent years, the LTE (Long Term Evolution) standard for the third generation (3G) mobile communication system has been studied in the standardization project “3GPP: 3rd Generation Partnership Project”. One of the issues to be studied is a radio resource allocation method for each user (radio terminal) in a radio system using a code multiplexing scheme in the uplink (radio link in the direction from the radio terminal to the radio base station), and There is a method of mapping radio resources allocated to each user. For example, in the prior art described in Non-Patent Document 1, in the uplink, a scheduling request signal (SR: Scheduling Request) and a data signal (PUSCH data) are simultaneously transmitted by frequency division multiplexing.
3GPP, R1-070717, “Interference between Data and Preamble-Based Scheduling Request in E-UTRAN”, Texas Instruments, Feb. 12-16, 2007. 3GPP, R1-072858, “Preamble Based Scheduling Request”, Texas Instruments, June 25-29, 2007. 3GPP, R1-072859, “Scheduling Request and DRX in E-UTRA”, Texas Instruments, June 25-29, 2007. 3GPP, R1-072688, “Performance of Scheduling Request using Contention Free Channel”, Motorola, June 25-29, 2007.

  However, in the conventional technology described in Non-Patent Document 1 described above, interference between the scheduling request signal (SR) and the data signal (Data) may occur as shown in FIGS. For this reason, the signal may not be received normally. In the 3GPP TSG RAN WG1 Meeting # 49bis meeting, it has been agreed to use a dedicated channel for transmission of scheduling request signals. Therefore, the scheduling request signal and the data signal are transmitted using different channels. The scheduling request signal is a signal for requesting scheduling to the base station in order for the user to secure his / her own wireless communication period.

  The present invention has been made in view of such circumstances, and its purpose is to use a dedicated channel different from a data channel for transmission of a scheduling request signal in an uplink of a radio system such as an E-UTRA system. An object of the present invention is to provide a wireless terminal device and a wireless base station device that can be used.

  In order to solve the above problems, a radio terminal apparatus according to the present invention transmits a scheduling request signal to be transmitted to a radio base station apparatus, and a response (ACK / NACK) signal (ACK / NACK :) to be transmitted to the radio base station apparatus. ACKnowledgement / Negative ACKnowledement) and orthogonal code division multiplexing means for orthogonal code division multiplexing between CQI (Channel Quality Indicator) signals, and the same time zone and the same frequency of the orthogonal code division multiplexed signals And wireless transmission means for transmitting in a band.

  A radio base station apparatus according to the present invention includes radio receiving means for receiving a radio signal, which is orthogonal code division multiplexed in the same time band and the same frequency band, from a radio terminal apparatus, and orthogonal code division multiplexing from the received signal. And a decoding means for separating a scheduling request signal, a response (ACK / NACK) signal, and a CQI signal.

  A radio terminal apparatus according to the present invention, a scheduling request signal to be transmitted to a radio base station apparatus, between an orthogonal code division multiplexed response (ACK / NACK) signal and a CQI signal to be transmitted to the radio base station apparatus Time division multiplexing means for time division multiplexing and radio transmission means for transmitting the time division multiplexed signal in the same frequency band are provided.

  A radio base station apparatus according to the present invention includes radio receiving means for receiving a radio signal time-division multiplexed in the same frequency band from a radio terminal apparatus, and a scheduling request signal and orthogonal code division multiplex from the received signal. Time division demultiplexing means for separating a response (ACK / NACK) signal and a CQI signal is provided.

  A radio terminal apparatus according to the present invention includes code division multiplexing means for code-division multiplexing a scheduling request signal to be transmitted to a radio base station apparatus with a random access channel signal to be transmitted to the radio base station apparatus, and the code And wireless transmission means for transmitting the converted signals in the same time band and the same frequency band.

  A radio base station apparatus according to the present invention includes radio receiving means for receiving a radio signal code division multiplexed from the radio terminal apparatus in the same time zone and the same frequency band, and scheduling that is code division multiplexed from the received signal. And a decoding means for separating the request signal and the random access channel signal.

  According to the present invention, a dedicated channel different from a data channel can be used for transmission of a scheduling request signal in an uplink of a radio system such as an E-UTRA system.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present embodiment, a third generation mobile communication system studied by 3GPP will be described as an example of a radio system using a code multiplexing scheme in uplink.

[First Embodiment]
In the first embodiment, a scheduling request signal, a response (ACK / NACK) signal (ACK or NACK), and a CQI (Channel Quality Indicator) signal are orthogonal code division multiplexed (orthogonal CDM) in the uplink of the wireless system. The response (ACK / NACK) signal and the CQI signal are control signals transmitted from the user to the base station using the control channel.

  FIG. 3 is a radio channel configuration diagram for explaining a radio transmission scheme for a scheduling request signal according to the first embodiment of the present invention. In FIG. 3A, the scheduling request signal, the response (ACK / NACK) signal, and the CQI signal are orthogonally encoded by CAZAC code (Zadoff-Chu), respectively. The orthogonally coded scheduling request signal, response (ACK / NACK) signal, and CQI signal are orthogonally code-division multiplexed using channels configured in the same time band and the same frequency band.

  As shown in FIG. 3 (2), how many bands are prepared in the frequency direction is controlled according to the number of active users in the base station, and a broadcast channel (BCH) is used from the base station to all users. And notify at a slow interval.

  In the scheduling request signal channel, it is preferable to change the use frequency by the frequency hopping method. By applying the frequency hopping method, it is possible to suppress degradation of reception characteristics due to frequency selective fading.

[Second Embodiment]
In the second embodiment, the scheduling request signal, the response (ACK / NACK) signal, and the CQI signal are time division multiplexed (TDM) in the uplink of the radio system.

  FIG. 4 is a radio channel configuration diagram for explaining a radio transmission method of a scheduling request signal according to the second embodiment of the present invention. In FIG. 4 (1), the scheduling request signal is time-division multiplexed and transmitted using a channel having the same frequency band and different time bands as the response (ACK / NACK) signal and the CQI signal. The response (ACK / NACK) signal and the CQI signal are orthogonally encoded by CAZAC codes, respectively, and orthogonal code division multiplexed transmission is performed using channels configured in the same time band and the same frequency band.

  As shown in FIG. 4 (2), how many bands are prepared in the frequency direction is controlled according to the number of active users in the base station, and a broadcast channel (BCH) is used from the base station to all users. And notify at a slow interval.

  In the scheduling request signal channel, it is preferable to change the use frequency by the frequency hopping method. By applying the frequency hopping method, it is possible to suppress degradation of reception characteristics due to frequency selective fading.

  According to the first and second embodiments described above, orthogonal multiplexing is possible. In addition, according to the first embodiment and the second embodiment, the radio resource allocation method using the same frequency hopping scheme as the response (ACK / NACK) signal channel and the CQI signal channel is applied to the scheduling request signal channel. Can be applied. Also, it is desirable to apply a radio resource allocation method using the same frequency hopping method from the viewpoint of realizing flexible radio resource distribution with the shared data channel and the simplicity of specifications.

[Third Embodiment]
In the third embodiment, a scheduling request signal and a random access channel (RACH: Random Access Channel) signal are code division multiplexed (CDM) in the uplink of a wireless system. The encoded scheduling request signal and RACH signal are transmitted using channels configured in the same time band and the same frequency band. This method can be transmitted only once in 10ms due to RACH restrictions. For this reason, it is necessary to transmit signals of many users at once, and orthogonal CDM is difficult due to the limitation of the number of code sequences.

  As mentioned above, although embodiment of this invention was explained in full detail with reference to drawings, the specific structure is not restricted to this embodiment, The design change etc. of the range which does not deviate from the summary of this invention are included.

It is explanatory drawing for demonstrating the radio | wireless transmission system of the conventional scheduling request signal. It is explanatory drawing for demonstrating the radio | wireless transmission system of the conventional scheduling request signal. It is a radio channel block diagram for demonstrating the radio | wireless transmission system of the scheduling request signal which concerns on 1st Embodiment of this invention. It is a radio channel block diagram for demonstrating the radio | wireless transmission system of the scheduling request signal which concerns on 2nd Embodiment of this invention.

Explanation of symbols

SR: Scheduling request signal

Claims (4)

In an E-UTRA wireless system in which a control channel that transmits a control signal including a response (ACK / NACK) signal and a CQI signal and a data channel that transmits a data signal are arranged in different frequency bands in the uplink,
Time division multiplexing means for time division multiplexing a scheduling request signal to be transmitted to a radio base station apparatus between an orthogonal code division multiplexed response (ACK / NACK) signal and a CQI signal to be transmitted to the radio base station apparatus When,
Wireless transmission means for transmitting the time-division multiplexed signal in the same frequency band of the control channel ;
A wireless terminal device comprising:   The time division multiplexing means performs time division multiplexing of a scheduling request signal in subframe units between a response (ACK / NACK) signal and an CQI signal that are orthogonally encoded in slot units. Item 2. The wireless terminal device according to Item 1. In an E-UTRA wireless system in which a control channel that transmits a control signal including a response (ACK / NACK) signal and a CQI signal and a data channel that transmits a data signal are arranged in different frequency bands in the uplink,
Radio receiving means for receiving a radio signal time-division multiplexed in the same frequency band of the control channel from a radio terminal device;
Time division demultiplexing means for separating a scheduling request signal and an orthogonal code division multiplexed response (ACK / NACK) signal and a CQI signal from the received signal;
A radio base station apparatus comprising:   The said scheduling request signal is time division multiplexed by the sub-frame unit between the response (ACK / NACK) signal and CQI signal which were orthogonally encoded by the slot unit. Wireless base station equipment.

Images