wireless communication device

Abstract

To provide a wireless communication device which suppresses lowering of a transmission rate and interference by an interference source in wireless communication.SOLUTION: A base station 1 includes: a consecutive-transmission control unit 12 which creates a plurality of transmission packets by copying transmission data to be transmitted to a plurality of mobile stations; a plurality of consecutively-transmitting units 17a and 17b which consecutively-transmit the plurality of transmission packets to the plurality of mobile stations in a frequency hopping system; a timing control unit 14 which determines transmission timing of the plurality of transmission packets in the plurality of RF units; and an FH control unit 16 which controls a frequency hopping pattern and frequency switching timing of each of the plurality of RF units. At least two transmission packets among the plurality of transmission packets are simultaneously transmitted in respectively different frequency bands from different RF units.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present disclosure relates to wireless communication devices. [Background technology]

[0002] When wireless communication is performed between wireless communication devices in a wireless communication system, if there is an interference source in the channel being used due to the surrounding wireless conditions, the device may receive a wireless signal other than the desired wireless signal, resulting in receiving an incorrect signal or not being able to receive the desired signal.This situation is called interference.

[0003] In conventional wireless communication systems, as a countermeasure to prevent reception of a desired wireless signal from being hindered by an interference signal transmitted from an interference source, the frequency channel is changed at a predetermined switching period, and the same data generated from the same transmission data is transmitted to the communication partner at different switching periods, thereby realizing highly reliable wireless communication even in an environment where an interference source is present (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 5823049 (pages 6-9, Figure 2) Summary of the Invention [Problem to be solved by the invention]

[0005] In the wireless communication system of Patent Document 1, the interference avoidance effect was improved by increasing the number of consecutive transmissions of the same train control information in multiple frames, but there was a problem in that the transmission rate was reduced by the number of consecutive transmissions.

[0006] The present disclosure has been made to solve the above-mentioned problems, and aims to suppress a decrease in transmission rate and interference caused by an interference source in wireless communication. [Means for solving the problem]

[0007] The wireless communication device of the present disclosure includes a plurality of communication units that communicate with other wireless communication units using a frequency hopping method, a continuous transmission control unit that copies transmission data to be transmitted to the other wireless communication units to create a plurality of transmission packets, a plurality of communication units that continuously transmit the plurality of transmission packets to the other wireless communication units using a frequency hopping method, a timing control unit that determines the transmission timing of the plurality of transmission packets in the plurality of communication units, and a frequency hopping control unit that controls the frequency hopping pattern and frequency switching timing of each of the plurality of communication units, and at least two of the plurality of transmission packets are simultaneously transmitted from different communication units in different frequency bands. [Effects of the Invention]

[0008] The wireless communication device of the present disclosure transmits multiple transmission packets in succession in different frequency bands, and transmits at least two of the transmission packets simultaneously, thereby making it possible to suppress a decrease in transmission rate and interference from an interference source. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a diagram illustrating an example of the configuration of a wireless communication system according to first and second embodiments. [Figure 2] FIG. 2 is a diagram illustrating an example of a frame format according to the first embodiment. [Figure 3] FIG. 1 is a diagram illustrating a conventional frame format. [Figure 4] FIG. 2 is a block diagram showing a configuration example of a base station according to the first embodiment. [Figure 5] FIG. 2 is a block diagram showing an example of the configuration of a mobile station according to the first embodiment. [Figure 6] FIG. 2 is a diagram illustrating an interference pattern that one interference source causes to wireless communication according to the first embodiment. [Figure 7] FIG. 1 illustrates an interference pattern caused by one interference source on conventional wireless communication. [Figure 8]It is a diagram showing an interference pattern given by a plurality of interference sources to the wireless communication of Embodiment 1. [Figure 9] It is a diagram showing an interference pattern given by a plurality of interference sources to conventional wireless communication. [Figure 10] It is a diagram showing an interference pattern given by interference sources having the same frequency band to the wireless communication of Embodiment 1. [Figure 11] It is a diagram showing an interference pattern given by interference sources having the same frequency band to conventional wireless communication. [Figure 12] It is a block diagram showing a configuration example of the base station of Embodiment 2. [Figure 13] It is a block diagram showing a configuration example of the mobile station of Embodiment 2. [Figure 14] It is a diagram showing the hardware configurations of the base stations and mobile stations of Embodiments 1 and 2. [Figure 15] It is a diagram showing the hardware configurations of the base stations and mobile stations of Embodiments 1 and 2.

MODE FOR CARRYING OUT THE INVENTION

[0010] <A. Embodiment 1> <A-1. Configuration> FIG. 1 is a diagram showing a configuration example of a wireless communication system 101 according to Embodiment 1. The configuration of a wireless communication system 102 according to Embodiment 2 described later is also the same as that of the wireless communication system 101. The wireless communication system 101 includes base stations 1-1, 1-2, 1-3 which are wireless communication devices, mobile stations 4, 5 which are wireless communication devices, and a central command room 3 that transmits and receives data or makes calls with the mobile stations 4, 5. The base stations 1-1, 1-2, 1-3 are arranged at a certain interval so that communication with the mobile stations 4, 5 can be continuously maintained. The base stations 1-1, 1-2, 1-3 are connected to each other by an inter-base station network 2, and information can be transmitted and received to and from the central command room 3 via the inter-base station network 2. The mobile stations 4, 5 can communicate at a fixed position without moving depending on the operation mode.

[0011] 1 shows three base stations 1-1, 1-2, and 1-3, but the number of base stations included in the wireless communication system 101 is not limited to three. In the following description, the base stations 1-1, 1-2, and 1-3 will be collectively referred to as base station 1.

[0012] FIG. 2 shows an example of a frame format used in the wireless communication system 101, and FIG. 3 shows a conventional frame format. In FIGS. 2 and 3, frame Fr-n (n is a natural number) is time-divided into downlink slots and uplink slots. The downlink slots include broadcast slot Bch and slots D1-D9. The uplink slots include slots U1-U9. Broadcast slot Bch is the first slot of the frame and contains broadcast information or frame configuration information, etc. Slots D1-D9 are allocated for downlink communication from base station 1 to mobile stations 4 and 5, and slots U1-U9 are allocated for uplink communication from mobile stations 4 and 5 to base station 1.

[0013] To improve the reliability of information, the same information is transmitted multiple times using multiple frames. In the examples of Figures 2 and 3, one piece of information is transmitted four times, i.e., four consecutive transmissions. For example, in Figure 2, the same number (1) is assigned to four consecutive frames Fr-1 to Fr-4, which indicates that frames Fr-1 to Fr-4 contain the same data. Similarly, four consecutive frames, frames Fr-5 to Fr-8, Fr-9 to Fr-12, and Fr-13 to Fr-16, each contain the same data. However, the number of consecutive transmissions is not limited to this.

[0014] In this embodiment, in order to avoid interference with other systems, frequency hopping (FH) is performed with a frequency switching period of one frame. In the example of Fig. 2, frame Fr-1 is transmitted on frequency ch1, frame Fr-2 is transmitted on frequency ch7, frame Fr-3 is transmitted on frequency ch3, and frame Fr-4 is transmitted on frequency ch5. Thereafter, the frequency is switched for each frame. In this way, the frequency is switched for each frame, and the same data is transmitted on multiple frequency channels by continuously transmitting each frame.

[0015] When transmission is performed using a single frequency channel, the presence of an interfering signal on that frequency channel can cause problems with information transmission. In contrast, by switching frequencies on a frame-by-frame basis and transmitting continuously, even if an interfering signal is present on one frequency channel, information can be transmitted using other frequency channels, improving reliability. Hereinafter, this is referred to as interference avoidance capability.

[0016] However, in the conventional frame format shown in FIG. 3, only one frame is transmitted at a time, and therefore, the transmission rate drops significantly as the number of consecutive transmissions increases.

[0017] Although the same problem occurs with the frame format of this embodiment shown in FIG. 2, since two frames are sent simultaneously, a transmission rate twice as high as that of the conventional frame format shown in FIG. 3 can be obtained.

[0018] Fig. 4 is a block diagram showing the configuration of a base station 1 in a wireless communication system 101. As shown in Fig. 4, the base station 1 is configured to include encoding units 11 and 13, a continuous transmission control unit 12, a timing control unit 14, a modulation unit 15, a frequency hopping (FH) control unit 16, RF (Radio Frequency) units 17a and 17b, a demodulation unit 18, an error correction unit 19, an identical packet deletion unit 20, a scheduler 21, and antennas 22a and 22b. The RF units 17a and 17b and the antennas 22a and 22b are collectively referred to as a communication unit.

[0019] The encoding unit 11 generates encoded data S2 by encoding transmission data S1 to be transmitted to mobile stations 4 and 5 within the cell under the jurisdiction of the base station 1.

[0020] The continuous transmission control unit 12 copies the coded data S2 into a plurality of transmission packets S3 and controls the continuous transmission.

[0021] The scheduler 21 generates broadcast information and frame configuration information S4 by allocating data to each of the time-divided uplink and downlink slots. The frame configuration information indicates the frame configuration and includes information on the destination of data for each slot.

[0022] The encoding unit 13 encodes the broadcast information and frame configuration information S4 generated by the scheduler 21 to generate a transmission packet S5.

[0023] The timing control unit 14 controls the transmission timing of the transmission packets S3 and S5, i.e., the output timing to the modulation unit 15, based on the frame configuration information from the scheduler 21, and generates transmission packet information S6 for each slot based on the transmission packets S3 and S5 and outputs it to the modulation unit 15. The timing control unit 14 also controls the reception timing of reception packets addressed to the own station based on the frame configuration information, and outputs a reception packet S13 addressed to the own station out of the demodulated signal S12 generated by the demodulation unit 18 to the error correction unit 19.

[0024] The modulation unit 15 generates baseband modulated signals S7a and S7b by modulating the transmission packet information S6 in each slot, and outputs the baseband modulated signals S7a and S7b to the RF units 17a and 17b.

[0025] The FH control unit 16 manages the frequency hopping pattern and frequency switching timing to be used for each of the base stations 1-1, 1-2, and 1-3, and outputs frequency control information S8a and S8b that specifies the RF frequency to the RF units 17a and 17b at each switching timing based on the information that it manages.

[0026] During transmission, RF unit 17a converts baseband modulated signal S7a into high-frequency signal S9a at an RF frequency specified by frequency control information S8a. During reception, RF unit 17a converts high-frequency signal S10a received by antenna 22a into baseband received signal S11a based on frequency control information S8a. Similarly, during transmission, RF unit 17b converts baseband modulated signal S7b into high-frequency signal S9b at an RF frequency specified by frequency control information S8b. During reception, RF unit 17b converts high-frequency signal S10b received by antenna 22b into baseband received signal S11b based on frequency control information S8b.

[0027] Antenna 22a emits high-frequency signal S9a as radio waves, and receives the radio waves and outputs them to RF unit 17a as high-frequency signal S10a. Similarly, antenna 22b emits high-frequency signal S9b as radio waves, and receives the radio waves and outputs them to RF unit 17b as high-frequency signal S10b.

[0028] The demodulator 18 demodulates the baseband received signals S11a and S11b to generate a demodulated signal S12.

[0029] The error correction unit 19 performs error correction on the received packet S13 to generate received information S14.

[0030] The identical packet deletion unit 20 generates the final demodulator output S15 by deleting redundant portions of the continuously transmitted received information S14. For example, if four pieces of identical data are transmitted continuously, the identical packet deletion unit 20 selects one of the four pieces of identical data for which error correction has been correctly performed, sets it as the demodulator output S15, and deletes the other three pieces of identical data. If there are multiple pieces of identical data for which error correction has been correctly performed, the identical packet deletion unit 20 selects one of them as the demodulator output S15 and deletes the other pieces of identical data.

[0031] Fig. 5 is a block diagram showing the configuration of mobile stations 4 and 5 in a wireless communication system 101. As shown in Fig. 5, the mobile stations 4 and 5 are configured to include an encoding unit 11, a continuous transmission control unit 12, a timing control unit 14, a modulation unit 15, an FH control unit 16, RF units 17a and 17b, a demodulation unit 18, an error correction unit 19, a duplicate packet deletion unit 20, antennas 22a and 22b, and a broadcast channel analysis unit 24. In Fig. 5, components of the mobile stations 4 and 5 that have the same functions as those of the base station 1 are given the same reference numerals, and duplicated explanations will be omitted. The mobile stations 4 and 5 are configured by deleting the scheduler 21 and the encoding unit 13 from the configuration of the base station 1 and adding the broadcast channel analysis unit 24.

[0032] The broadcast channel analysis unit 24 analyzes the broadcast channel information contained in the demodulator output S15 to generate transmission and reception timing information of its own station (the result of the allocation of communication time slots) and FH frequency information S16, and inputs the transmission and reception timing information to the timing control unit 14 and the FH frequency information S16 to the FH control unit 16.

[0033] 4 and 5, the base station 1 and the mobile stations 4 and 5 each have two RF units 17a and 17b and two antennas 22a and 22b. This allows the base station 1 and the mobile stations 4 and 5 to transmit simultaneously on two frequency channels. Although the transmission speed can be further improved by further increasing the number of RF units and antennas, the maximum number of RF units and antennas is the same as the number of frequency hopping channels.

[0034] <A-2. Operation> The operation of the base station 1 of the present embodiment will be described using FIG. 4.

[0035] First, the scheduler 21 performs scheduling as shown in FIG. 2 for each mobile station 4, 5 accommodated in its own cell, determines the slots used by each mobile station 4, 5 for the downlink and uplink respectively, generates frame configuration information, and generates notification information. The notification information includes information forming the frequency hopping pattern information for each mobile station 4, 5 and information on the transmission timing. That is, the scheduler 21 prevents interference between mobile stations by allocating communication time bands to each mobile station in the same cell in a time division manner. Further, the notification information includes the frequency hopping information managed by the FH control unit 16.

[0036] The FH control unit 16 has a plurality of frequency hopping patterns and has a function of adjusting the hopping patterns so that each hopping pattern does not use the same frequency at the same time.

[0037] Next, the encoding unit 11 encodes the transmission data S1 for each mobile station 4, 5 obtained from the central command room 3 via the base station network 2 to create encoded data S2. Then, the concatenation control unit 12 performs a replication process for concatenation to generate a transmission packet S3.

[0038] The timing control unit 14 allocates the transmission packet S3 for each mobile station 4, 5 to each slot based on the frame configuration information from the scheduler 21 and sends it to the modulation unit 15 as transmission packet information S6.

[0039] The modulator 15 generates baseband modulated signals S7a and S7b at a transmission timing that avoids interference with other systems and sends them to the RF units 17a and 17b. The modulator 15 not only modulates signals for wireless transmission but also distributes the same signal to the RF units 17a and 17b. Here, the FH controller 16 manages the frequency hopping patterns and switching timings to be used for each base station 1-1, 1-2, and 1-3, and outputs frequency control information S8a and S8b that specifies the RF frequency to the RF units 17a and 17b at each switching timing based on this information. The FH controller 16 may be configured as one or more units, but each frequency hopping pattern is linked to the frequency hopping pattern of the corresponding RF, and control is performed to ensure that the same channel is not used for the RF at the same time.

[0040] The RF units 17a and 17b convert the baseband modulation signals S7a and S7b into high-frequency signals in a specified high-frequency band based on the frequency control information S8a and S8b, and generate amplified high-frequency signals S9a and S9b, which are then transmitted from the antennas 22a and 22b, respectively.

[0041] The demodulation unit 18 demodulates the baseband received signals S11a and S11b and combines them into a single signal form to generate a demodulated signal S12. Of the demodulated signal S12, a received packet S13 addressed to the station is output by the timing control unit 14 to an error correction unit 19. The error correction unit 19 performs error correction on the received packet S13. Thereafter, when all identical signals have been collected, the identical packet deletion unit 20 deletes unnecessary signals.

[0042] Base station 1 of this embodiment differs from conventional base stations in that it transmits multiple frames containing the same information at the same time using two frequencies. Therefore, base station 1 has two RF units 17a and 17b, and modulator 15 has a function of distributing the same signal to RF units 17a and 17b.

[0043] Next, the operations of the mobile stations 4 and 5 according to the present embodiment will be described using FIG. 5. The operations of the mobile stations 4 and 5 are substantially the same as those of the base station 1, except that the transmission / reception timing information of its own station and the frequency information S16 of frequency hopping are obtained from the notification information received from the base station 1.

[0044] That is, in the mobile stations 4 and 5, the notification channel analysis unit 24 analyzes the notification information from the base stations 1-1, 1-2, and 1-3, synchronizes the time between the base stations 1-1, 1-2, and 1-3, and synchronizes the start timing of the frequency hopping pattern and the start timing of the frequency switching period between the base stations 1-1, 1-2, and 1-3. At the same time, the notification channel analysis unit 24 acquires the slot number assigned to its own station and the frequency information S16 of frequency hopping such as the frequency hopping pattern used by the base stations 1-1, 1-2, and 1-3. Based on these pieces of information, the mobile stations 4 and 5 avoid interference with other systems and perform transmission and reception with the base stations 1-1, 1-2, and 1-3.

[0045] The mobile stations 4 and 5 according to the present embodiment are different from the conventional mobile stations in that they include two RF units 17a and 17b, the modulation unit 15 has a function of distributing the same signal to the two RF units 17a and 17b, the demodulation unit 18 demodulates the two signals respectively and then performs error correction by the error correction unit 19, and when all the same signals are gathered, the unnecessary signals are deleted by the same packet deletion unit 20. These points are the same as those of the base station 1.

[0046] <A-3. Effect> FIG. 6 is a diagram showing an interference pattern given by one interference source to the wireless communication of Embodiment 1. FIG. 7 is a diagram showing an interference pattern given by one interference source to the conventional wireless communication. In both cases of FIGS. 6 and 7, it is assumed that the number of consecutive transmissions is 4 and the number of channels is 8ch. The transmission schedule shown in FIG. 6 is the same as the transmission schedule shown in FIG. 2, and the transmission schedule shown in FIG. 7 is the same as the transmission schedule shown in FIG. 3.

[0047] The wireless communication of this embodiment achieves a transmission rate that is twice as high as that of conventional wireless communication, regardless of interference conditions.

[0048] 6 and 7 show interference patterns caused by a single interference source. Assume that this interference source has the same frequency band and slot length as the base station, and that the frequency hopping of the interference source follows the frequency hopping of the wireless communication system. In this case, in a conventional wireless communication system, as shown in FIG. 7, interference occurs in all channels, and signals may not be demodulated. However, in the wireless communication system of this embodiment, as shown in FIG. 6, even if one receiving channel, for example, channel 1, cannot be demodulated due to interference at the same timing, the other receiving channel, for example, channel 7, can be demodulated, so signals can be reliably demodulated even in the presence of interference.

[0049] Fig. 8 is a diagram showing an interference pattern caused by two interference sources on the wireless communication of the first embodiment. Fig. 9 is a diagram showing an interference pattern caused by two interference sources on the conventional wireless communication. In both Fig. 8 and Fig. 9, the number of consecutive transmissions is assumed to be four, and the number of channels is assumed to be eight. The transmission schedule shown in Fig. 8 is the same as the transmission schedule shown in Fig. 2, and the transmission schedule shown in Fig. 9 is the same as the transmission schedule shown in Fig. 3.

[0050] It is assumed that the two interference sources in Figures 8 and 9 have the same frequency band and slot length as the base station, and that the frequency hopping of these interference sources follows the frequency hopping of the wireless communication system. In this case, as shown in Figures 8 and 9, in both this embodiment and the conventional wireless communication system, interference may occur in all channels, making it impossible to demodulate signals. Nevertheless, it is clear that the probability that two frequency channels that simultaneously transmit data in wireless communication system 101 of this embodiment are both subject to interference by two interference sources is lower than the probability that one frequency channel is subject to interference by two interference sources in the conventional wireless communication system.

[0051] Specifically, assuming that the hopping pattern of the interference source is random, the probability that a signal cannot be demodulated due to interference in the frequency hopping pattern of this embodiment is (2 / x^2)^(n / 2). Here, x is the number of channels (ch), and n is the number of consecutive transmissions. Also, assuming that the hopping pattern of the interference source is random, the probability that a signal cannot be demodulated due to interference in the conventional frequency hopping pattern is (2x - (1 / (x^2)))^n. Comparing the two, the probability that the wireless communication of this embodiment avoids interference is improved by 2 / (2x - 1) times compared to the conventional wireless communication. That is, assuming that the number of consecutive transmissions is 4 times and the number of channels is 8ch, the interference avoidance ability of the wireless communication of this embodiment is improved by 197 times compared to the conventional one.

[0052] <B. Embodiment 2> FIG. 10 is a diagram showing the interference pattern given by four interference sources to the wireless communication of Embodiment 1. FIG. 11 is a diagram showing the interference pattern given by four interference sources to the conventional wireless communication. In both cases of FIG. 10 and FIG. 11, it is assumed that the number of consecutive transmissions is 4 times and the number of channels is 8ch. The transmission schedule shown in FIG. 10 is the same as the transmission schedule shown in FIG. 2, and the transmission schedule shown in FIG. 11 is the same as the transmission schedule shown in FIG. 3. The four interference sources in FIGS. 10 and 11 are assumed to have the same frequency band as the base station and not to perform frequency hopping.

[0053] In the wireless communication systems of Embodiment 1 and the conventional one, the same data is consecutively transmitted by four frequency channels (ch). When there is one interference source, even if one frequency channel overlaps with the interference source, data can be transmitted and received by the remaining three frequency channels. Therefore, in any wireless communication system, there is no pattern in which a signal cannot be demodulated due to interference.

[0054] However, as shown in Figures 10 and 11, when there are four interference sources, all four frequency channels that transmit the same data repeatedly may overlap with the interference sources, and the signal may not be demodulated. When there are the same number of interference sources as the number of continuous transmissions, in the first embodiment and the conventional wireless communication system, the probability that the signal cannot be demodulated due to interference is ((x-2) / x)^n, where x is the number of channels and n is the number of continuous transmissions.

[0055] Assuming there are four consecutive transmissions and eight channels, the probability that a signal cannot be demodulated due to interference depends on the length of the superframe. For example, if the length of the superframe is one period of the frequency hopping pattern, one signal will always be unable to be demodulated due to interference. On the other hand, if the length of the superframe is shorter than one period of the frequency hopping pattern, the probability that a signal cannot be demodulated due to interference is x(x-1)(x-2)(x-3) / ((x(x-1)(x-2)(x-3))^a), where x is the number of channels and a is the number of frequency hopping patterns.

[0056] In other words, assuming four consecutive transmissions and eight channels, 1,680 types of data transmission are required to cover all frequency hopping patterns, and when 1,680 types of data transmission are used as one superframe, one signal will definitely not be demodulated. On the other hand, when 20 types of data transmission are used, the probability that a signal cannot be demodulated due to interference is 1-(1,679 x 1,680)^20, or approximately 1.2%.

[0057] Therefore, in the wireless communication system 102 of Embodiment 2, before installing the base station 1 and the mobile stations 4 and 5, the interference source is checked, and interference avoidance is performed by appropriately selecting a frequency hopping pattern. Alternatively, as shown in FIGS. 12 and 13, the base station 1 and the mobile stations 4 and 5 are provided with a carrier sense unit 23, and the carrier sense unit 23 constantly checks for interference sources and performs interference avoidance by appropriately selecting a frequency hopping pattern. Specifically, the carrier sense unit 23 constantly determines whether a channel ch has interference from an interference source or not, and forms a frequency hopping pattern such that all channels within a continuous transmission do not become channels with interference. In this case, although it is conceivable to reduce the number of patterns of the frequency hopping pattern, the usage rate within a certain time for each channel is made constant.

[0058] In Embodiment 2, the case where a carrier sense unit having a higher interference avoidance effect can avoid interference even when the number of interference sources increases after the installation of the device will be described. However, it is also possible to enable interference avoidance by checking for interference sources before installing the device and appropriately selecting a frequency hopping pattern.

[0059] <B-1. Configuration> The overall configuration of the wireless communication system 102 of Embodiment 2 is as shown in FIG. 1 and is the same as that of the wireless communication system 101 of Embodiment 1.

[0060] FIG. 12 is a block diagram showing the configuration of the base station 1 in the wireless communication system 102. FIG. 13 is a block diagram showing the configuration of the mobile stations 4 and 5 in the wireless communication system 102.

[0061] As shown in FIG. 12, the base station 1 according to Embodiment 2 includes a carrier sense unit 23 in addition to the configuration of the base station 1 according to Embodiment 1. Also, as shown in FIG. 13, the mobile stations 4 and 5 according to Embodiment 2 include a carrier sense unit 23 in addition to the configuration of the mobile stations 4 and 5 according to Embodiment 1. The carrier sense unit 23 has a function of checking whether other wireless devices are using the same radio channel before the wireless communication system 102 starts transmission and appropriately selecting a frequency hopping pattern.

[0062] The carrier sense unit 23 of the base station 1 performs carrier sense to generate carrier sense information S17, and outputs the generated carrier sense information S17 to the scheduler 21. The carrier sense units 23 of the mobile stations 4 and 5 perform carrier sense to generate carrier sense information S17, and output the generated carrier sense information S17 to the notification channel analysis unit 24. The carrier sense unit 23 monitors the surrounding interference situation based on the baseband reception signals S11a and S11b output from the RF units 17a and 17b during carrier sense, thereby collecting information that enables optimization of the frequency hopping pattern. Here, the surrounding interference situation includes the frequency of the interference source in the radio system environment, the information of the interference timing in terms of time, and the form of interference in the steady state.

[0063] <B-2. Operation> In the mobile stations 4 and 5, the carrier sense unit 23 performs carrier sense to generate carrier sense information S17, and outputs it to the notification channel analysis unit 24. The notification channel analysis unit 24 adds the information of the interference source included in the carrier sense information S17 obtained from the carrier sense unit 23 to the transmission packet S5. Thus, the mobile stations 4 and 5 transmit the interference situation around themselves to the base station 1 simultaneously with the main signal.

[0064] In the base station 1, the carrier sense unit 23 performs carrier sense to generate carrier sense information S17, and outputs it to the scheduler 21. Here, the carrier sense information S17 output to the scheduler 21 includes information indicating the interference situation around the base station 1 and information indicating the interference situation around the mobile stations 4 and 5 created by the mobile stations 4 and 5. The scheduler 21 forms a frequency hopping pattern that does not overlap with at least one of the interference sources around the base station 1 and the mobile stations 4 and 5 based on the interference situations around the base station 1 and the mobile stations 4 and 5. In addition, as long as a frequency hopping pattern that can avoid interference can be formed, the formation method is not limited.

[0065] The carrier sense information S17 includes information on the frequency of the interference source and the interference timing. Further, the carrier sense information S17 may include the output level of the interference and the transition pattern of the frequency hopping of the interference source. Note that the carrier sense unit 23 of the mobile station 4 may not perform carrier sense.

[0066] <B-3. Effect> As described above, according to the wireless communication system 102, by optimizing the frequency hopping pattern after grasping the interference situation caused by the interference source, it is possible to avoid interference even when the number of interference sources is equal to the number of consecutive transmissions. Further, since the base station 1 and the mobile stations 4 and 5 are provided with the carrier sense unit 23, it is possible to avoid interference even when the number of interference sources increases after the installation of the base station 1 and the mobile stations 4 and 5.

[0067] <C. Hardware Configuration> The encoding unit 11, the consecutive transmission control unit 12, the timing control unit 14, the modulation unit 15, the FH control unit 16, the RF units 17a and 17b, the demodulation unit 18, the error correction unit 19, and the duplicate packet deletion unit 20 in the base station 1 or the mobile stations 4 and 5 described above, the encoding unit 13 and the scheduler 21 in the base station 1, and the notification channel analysis unit 24 in the mobile stations 4 and 5 are realized by the processing circuit 81 shown in FIG. 14. That is, the processing circuit 81 includes the encoding unit 11, the consecutive transmission control unit 12, the timing control unit 14, the modulation unit 15, the FH control unit 16, the RF units 17a and 17b, the demodulation unit 18, the error correction unit 19, and the duplicate packet deletion unit 20, the encoding unit 13, the scheduler 21, and the notification channel analysis unit 24 (hereinafter referred to as "encoding unit 11 etc."). A dedicated hardware may be applied to the processing circuit 81, or a processor that executes a program stored in a memory may be applied. The processor is, for example, a central processing unit, a processing device, an arithmetic device, a microprocessor, a microcomputer, a DSP (Digital Signal Processor), or the like.

[0068] When the processing circuit 81 is dedicated hardware, the processing circuit 81 may be, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a combination thereof. The functions of each unit such as the encoding unit 11 may be realized by multiple processing circuits 81, or the functions of each unit may be realized together by a single processing circuit.

[0069] When the processing circuit 81 is a processor, the functions of the encoding unit 11 and the like are realized by a combination of software, etc. (software, firmware, or software and firmware). The software, etc. is written as a program and stored in a memory. As shown in FIG. 15, a processor 82 applied to the processing circuit 81 realizes the functions of each unit by reading and executing a program stored in a memory 83. That is, the base station 1 or the mobile stations 4 and 5 include a memory 83 for storing a program that, when executed by the processing circuit 81, results in the function of each unit being executed. In other words, this program can be said to cause a computer to execute the procedure or method of the encoding unit 11 and the like. Here, the memory 83 may be, for example, a non-volatile or volatile semiconductor memory such as RAM (Random Access Memory), ROM (Read Only Memory), flash memory, EPROM (Erasable Programmable Read Only Memory), EEPROM (Electrically Erasable Programmable Read Only Memory), HDD (Hard Disk Drive), magnetic disk, flexible disk, optical disk, compact disk, mini disk, DVD (Digital Versatile Disk) and its drive device, or any storage medium to be used in the future.

[0070] The above describes a configuration in which each function of the encoding unit 11, etc. is realized either by hardware or software, etc. However, this is not a limitation, and a configuration in which part of the encoding unit 11, etc. is realized by dedicated hardware and another part is realized by software, etc. For example, the function of the FH control unit 16 can be realized by a processing circuit as dedicated hardware, and the other functions can be realized by the processing circuit 81 as the processor 82 reading and executing a program stored in the memory 83.

[0071] As described above, the processing circuit can realize each of the above-described functions by hardware, software, or a combination of these.

[0072] It is possible to freely combine the embodiments, and to modify or omit the embodiments as appropriate.

[0073] Various aspects of the present disclosure are summarized below as appendices.

[0074] (Appendix 1) a plurality of communication units that communicate with other wireless communication devices using a frequency hopping method; a continuous transmission control unit that copies transmission data to be transmitted to another wireless communication device and creates a plurality of transmission packets; a plurality of communication units that successively transmit the plurality of transmission packets to other wireless communication devices using a frequency hopping method; a timing control unit that determines transmission timings of the plurality of transmission packets in the plurality of communication units; a frequency hopping control unit that controls the frequency hopping pattern and frequency switching timing of each of the plurality of communication units, At least two of the plurality of transmission packets are simultaneously transmitted from different communication units in different frequency bands. Wireless communication device.

[0075] (Appendix 2) a broadcast channel analysis unit that analyzes broadcast channel information included in a signal received from another wireless communication device, and synchronizes the frequency hopping pattern and the switching timing with the other wireless communication device; 2. The wireless communication device of claim 1.

[0076] (Appendix 3) The frequency hopping patterns of the plurality of communication units do not use the same frequency at the same time. 3. The wireless communication device of claim 1 or 2.

[0077] (Appendix 4) The frequency hopping control unit controls the frequency hopping patterns of each of the plurality of communication units based on a result of carrier sense that confirms the frequencies used by surrounding interference sources. 2. The wireless communication device of claim 1.

[0078] (Appendix 5) Further comprising a carrier sense unit that performs the carrier sense. 5. The wireless communication device of claim 4. [Explanation of symbols]

[0079] 1,1-1,1-2,1-3 base station, 2 inter-base station network, 3 central control room, 4,5 mobile station, 11,13 encoding unit, 12 continuous transmission control unit, 14 timing control unit, 15 modulation unit, 16 FH control unit, 17a,17b RF unit, 18 demodulation unit, 19 error correction unit, 20 identical packet deletion unit, 21 scheduler, 22a,22b antenna, 23 carrier sense unit, 24 broadcast channel analysis unit, 81 processing circuit, 82 processor, 83 memory, 101,102 wireless communication system.

Claims

1. a plurality of communication units that communicate with other wireless communication devices using a frequency hopping method; a continuous transmission control unit that copies transmission data to be transmitted to another wireless communication device and creates a plurality of transmission packets; a plurality of communication units that successively transmit the plurality of transmission packets to other wireless communication devices using a frequency hopping method; a timing control unit that determines transmission timings of the plurality of transmission packets in the plurality of communication units; a frequency hopping control unit that controls the frequency hopping pattern and frequency switching timing of each of the plurality of communication units, At least two of the plurality of transmission packets are simultaneously transmitted from different communication units in different frequency bands. Wireless communication device.

2. a broadcast channel analysis unit that analyzes broadcast channel information included in a signal received from another wireless communication device, and synchronizes the frequency hopping pattern and the switching timing with the other wireless communication device; The wireless communication device of claim 1 .

3. the frequency hopping patterns of the plurality of communication units do not use the same frequency at the same time; 3. The wireless communication device according to claim 1.

4. The frequency hopping control unit controls the frequency hopping patterns of each of the plurality of communication units based on a result of carrier sense that confirms the frequencies used by surrounding interference sources. The wireless communication device of claim 1 .

5. Further comprising a carrier sense unit that performs the carrier sense.

5. The wireless communication device according to claim 4.

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