Communication device and its control method, program and storage medium

Abstract

In recent years, wireless communication has been used in a variety of applications, and there is a growing demand for highly convenient wireless communication solutions. [Solution] The image forming apparatus includes: receiving means for receiving a first trigger frame containing information regarding OFDMA compliant with the IEEE 802.11 standard from an external access point outside the image forming apparatus while the first mode is enabled; communication means for executing communication processing in the first mode using OFDMA compliant with the IEEE 802.11 standard based on the information regarding the first trigger frame; and control means for controlling the image forming apparatus so that OFDMA compliant with the IEEE 802.11 standard is not executed in the wireless communication of the second mode based on the fact that the second mode has been enabled, even if OFDMA compliant with the IEEE 802.11 standard is enabled in the first mode.

Description

Technical Field

[0001] The present invention relates to an image forming apparatus.

Background Art

[0002] A technique in which an image forming apparatus can execute wireless communication in infrastructure mode and wireless communication in ad hoc mode in parallel via an access point is disclosed in Patent Document 1.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In recent years, wireless communication has been used in various cases, and it is desired to provide highly convenient wireless communication.

Means for Solving the Problems

[0005] To solve the above problems, an image forming apparatus is provided, comprising: a first setting means for enabling a first mode in which wireless communication is performed via an external access point outside the image forming apparatus; a second setting means for enabling a second mode in which wireless communication is performed without going through an external access point outside the image forming apparatus; a receiving means for receiving a first trigger frame containing information about OFDMA compliant with the IEEE 802.11 standard from an external access point outside the image forming apparatus while the first mode is enabled; a communication means for performing communication processing in the first mode by OFDMA compliant with the IEEE 802.11 standard based on the information about the first trigger frame; a control means for controlling the image forming apparatus so that OFDMA compliant with the IEEE 802.11 standard is not performed in wireless communication of the second mode based on the fact that the second mode has been enabled, even if OFDMA compliant with the IEEE 802.11 standard is enabled in the first mode; and a printing processing means for performing printing processing on paper based on a print job received by wireless communication via the first mode or wireless communication via the second mode. [Effects of the Invention]

[0006] According to the present invention, it becomes possible to provide highly convenient wireless communication. [Brief explanation of the drawing]

[0007] [Figure 1] This figure shows an example of the system configuration in this embodiment. [Figure 2] (A) A diagram showing an example of the hardware configuration of a mobile terminal. (B) A diagram showing an example of the hardware configuration of an image forming apparatus. [Figure 3] This figure shows an example of the functional configuration of an access point. [Figure 4] This figure shows an example of communication processing. [Figure 5] This figure shows an example of a frame configuration. [Figure 6] This figure shows an example of a frame configuration. [Figure 7] This figure shows an example of a subchannel configuration. [Figure 8] This figure shows an example of communication processing. [Figure 9(A)] This figure shows an example of the user interface. [Figure 9(B)] This figure shows an example of the user interface. [Figure 9(C)] This figure shows an example of the user interface. [Figure 9(D)] This figure shows an example of the user interface. [Figure 10] This diagram shows a flowchart related to the processing of an image forming apparatus. [Figure 11] This diagram shows a flowchart related to the processing of an image forming apparatus. [Modes for carrying out the invention]

[0008] The embodiments of the present invention will be described in detail below with reference to the drawings. It should be noted that these embodiments are merely examples, and unless otherwise specified, the specific examples of components, processing steps, display screens, etc., are not intended to limit the scope of the present invention.

[0009] (System Configuration) Figure 1 shows an example of the system configuration according to this embodiment. In one example, this system is a wireless communication system in which multiple communication devices can communicate with each other wirelessly. In the example in Figure 1, the system includes an access point 131, an MFP 151, and a mobile terminal 101. An example of the mobile terminal 101 is a notebook computer or a smartphone.

[0010] The MFP151 has printing, scanning (scanning), and faxing functions. Furthermore, the MFP151 in this embodiment has a communication function that allows wireless communication with the mobile terminal 101. This embodiment describes the use of the MFP151 as an example, but is not limited to this. For example, a facsimile machine, scanner, projector, or single-function printer may be used instead of the MFP151. MFP is an abbreviation for Multi-Function Peripheral. In this embodiment, a device with printing capabilities may also be referred to as an image forming apparatus.

[0011] Access point 131 is located separately (externally) from the mobile terminal 101 and MFP 151, and operates as a base station device for wireless LAN (WLAN). Access point 131 may also be referred to as external access point 131 or external wireless base station (or external master station). MFP 151, which has WLAN communication capabilities, can communicate in WLAN infrastructure mode via access point 131. In the following, access point may be referred to as "AP". Infrastructure mode may also be referred to as "wireless infrastructure mode" or "infrastructure mode".

[0012] Infrastructure mode is a mode in which the MFP151 communicates with other devices via external devices (e.g., AP131) that form a network. The connection with the external AP established by the MFP151 operating in infrastructure mode is called an infrastructure connection (hereinafter referred to as an infrastructure connection). In this embodiment, in an infrastructure connection, the MFP151 operates as a slave station, and the external AP131 operates as a master station. In this embodiment, the master station is a device that forms a network and determines the communication channel used in that network. A slave station is a device that does not determine the communication channel used in the network to which it belongs, but performs wireless communication on the communication channel determined by the master station.

[0013] AP131 performs wireless communication with a communication device that has permitted (authenticated) connection to the device itself, and relays the wireless communication between that communication device and other communication devices. Also, for example, AP131 can be connected to a wired communication network and relay the communication between a communication device connected to that wired communication network and other communication devices wirelessly connected to access point 131.

[0014] Mobile terminal 101 and MFP151 can perform wireless communication in a wireless infrastructure mode via an external AP131 or in a peer-to-peer mode without using an external AP131, using the WLAN communication functions they each have. Hereinafter, peer-to-peer is referred to as "P2P". Alternatively, communication without using an external AP131 may be referred to as direct wireless communication. The P2P mode includes Wi-Fi Direct (registered trademark), soft AP mode, etc. Hereinafter, Wi-Fi Direct (registered trademark) may be referred to as WFD. The P2P mode can also be said to be communication compliant with the IEEE802.11 series.

[0015] The P2P mode is a form in which the MFP 151 communicates directly with other devices such as the mobile terminal 101 without going through an external device that forms a network. In this embodiment, it is assumed that the P2P mode includes an AP mode in which the MFP 151 operates as an AP. It is assumed that the connection information (SSID and password) of the AP enabled within the MFP 151 in the AP mode can be arbitrarily set by the user. Note that the P2P mode may include, for example, a WFD mode for the MFP 151 to communicate by Wi-Fi Direct (WFD). Which of the multiple WFD-compatible devices operates as the master station is determined, for example, according to a sequence called Group Owner Negotiation. Note that the master station may be determined without executing Group Owner Negotiation. A device that is a WFD-compatible device and serves as the master station is particularly called a Group Owner. A direct connection with other devices established by the MFP 151 operating in the P2P mode is called a direct connection. In this embodiment, in the direct connection, the MFP 151 operates as the master station and other devices (such as the mobile terminal 101) operate as slave stations.

[0016] Next, the configuration of the mobile terminal of this embodiment and the communication device capable of communicating with the mobile terminal of this embodiment will be described with reference to FIG. 2. In addition, in this embodiment, the following configuration is described as an example, but this embodiment is applicable to a device capable of communicating with a communication device, and the functions are not particularly limited as shown in this figure.

[0017] The mobile terminal 101 includes an input interface 102, a CPU 103, a ROM 104, a RAM 105, an external storage device 106, an output interface 107, a display unit 108, a keyboard 109, a communication unit 110, a short-range wireless communication unit 111, a network interface 112, a USB interface 113, etc. A computer of the mobile terminal 101 is formed by the CPU 103, the ROM 104, the RAM 105, etc.

[0018] The input interface 102 is an interface for receiving data input and operation instructions from the user when an operation unit such as a keyboard 109 is operated. The operation unit may be a physical keyboard or physical buttons, or it may be a soft keyboard or soft buttons displayed on the display unit 108. In other words, the input interface 102 may also receive input (operation) from the user via the display unit 108.

[0019] The CPU 103 is the system control unit and controls the entire mobile terminal 101. The ROM 104 stores fixed data such as control programs executed by the CPU 103, data tables, and embedded operating system (hereinafter referred to as OS) programs. In this embodiment, each control program stored in the ROM 104 performs software execution control such as scheduling, task switching, and interrupt handling under the management of the embedded OS stored in the ROM 104.

[0020] RAM105 consists of SRAM (Static Random Access Memory) and other components that require a backup power supply. Since RAM105's data is held by a primary battery (not shown) for data backup, important data such as program control variables can be stored without being lost. RAM105 also includes a memory area for storing the settings information and management data of the mobile terminal 101. Furthermore, RAM105 is used as both the main memory and work memory of the CPU 103.

[0021] The external storage device 106 stores, for example, a print information generation program that generates print information that can be interpreted by the printing device 115. The output interface 107 is an interface that controls the display unit 108 to display data and notify the status of the mobile terminal 101.

[0022] The display unit 108 consists of LEDs (light-emitting diodes) and LCDs (liquid crystal displays) and displays data and notifies the status of the mobile terminal 101. The communication unit 110 is configured to connect to devices such as the MFP 151 and access point (AP) 131 to perform data communication. For example, the communication unit 110 can connect to an AP (not shown) inside the MFP 151. By connecting the communication unit 110 to the AP inside the MFP 151, the mobile terminal 101 and the MFP 151 can communicate via P2P. The communication unit 110 may communicate directly with the MFP 151 via wireless communication, or it may communicate via an AP 131 unit located outside the mobile terminal 101 and the MFP 151. External devices include external APs (such as AP 131) located outside the mobile terminal 101 and the MFP 151, as well as devices other than APs that can relay communication. In this embodiment, the wireless communication method used by the communication unit 110 is Wi-Fi (WirelessFidelity) (registered trademark), which is a communication standard compliant with the IEEE 802.11 series. AP131 may be, for example, a wireless LAN router or other device.

[0023] The short-range wireless communication unit 111 is configured to wirelessly connect to devices such as the MFP 151 at short range and perform data communication, and communicates using a different communication method than the communication unit 110. The short-range wireless communication unit 111 can connect to, for example, the short-range wireless communication unit 157 in the MFP 151. Examples of communication methods include Near Field Communication (NFC), Bluetooth® Classic, Bluetooth Low Energy (BLE), and Wi-Fi Aware.

[0024] The network interface 112 is a connection interface that controls communication via wireless and communication processing via wired LAN cables.

[0025] The USB interface 113 is a connection interface that controls USB connections via a USB cable. Specifically, the USB interface 113 is an interface for connecting to devices such as the MFP151 and external AP131 via USB and performing data communication.

[0026] Next, I will explain the MFP151. The MFP151 includes a ROM152, RAM153, CPU154, print engine155, communication unit156, short-range wireless communication unit157, input interface158, operation unit159, output interface160, display unit161, network interface162, USB interface163, etc. The ROM152, RAM153, CPU154, etc. form the computer of the MFP151.

[0027] The communication unit 156 controls the communication processing using each interface. For example, the MFP 151 can operate in infrastructure mode and P2P (Peer to Peer) mode as modes for performing communication using the communication unit 156.

[0028] Specifically, the communication unit 156 can operate as an AP (Access Point) within the MFP 151. For example, the MFP 151 will operate as an AP if the user instructs it to activate the internal AP. In this embodiment, the wireless communication method used by the communication unit 156 is a communication standard compliant with the IEEE 802.11 series. In the following description, Wi-Fi (WirelessFidelity) (registered trademark) (Wi-Fi communication) refers to a communication standard compliant with the IEEE 802.11 series. The communication unit 156 may have hardware that functions as an AP, or it may operate as an AP (software AP mode) through software that enables it to function as an AP. When the communication unit 156 operates as a master station, it can maintain parallel P2P wireless connections with a predetermined number of slave station devices (e.g., 3 or fewer). The communication unit 156 can perform wireless communication using frequency bands selected from 2.4GHz, 5GHz, and 6GHz.

[0029] The short-range wireless communication unit 157 is configured to establish a short-range wireless connection with a device such as a mobile terminal 101, and can, for example, connect to the short-range wireless communication unit 111 within the mobile terminal 101. Examples of communication methods include NFC, Bluetooth Classic, BLE, and Wi-Fi Aware.

[0030] RAM153 consists of SRAM and other components that require a backup power supply. Since RAM153's data is held by a primary battery (not shown) for data backup, important data such as program control variables can be stored without being lost. RAM153 also includes a memory area for storing MFP151 configuration information and management data. Furthermore, RAM153 is used as the main memory and work memory for the CPU154, storing a receive buffer for temporarily saving print information received from mobile terminals such as the 101, and various other information.

[0031] ROM152 stores fixed data such as control programs, data tables, and OS programs executed by the CPU154. In this embodiment, each control program stored in ROM152 performs software execution control such as scheduling, task switching, and interrupt handling under the management of the embedded OS also stored in ROM152.

[0032] The CPU 154 is the system control unit and controls the entire MFP 151.

[0033] The print engine 155 performs a printing process to form an image on a recording medium by adding a recording material such as ink to paper, based on information stored in the RAM 153 or print jobs received from a mobile terminal 101, and outputs the print result. Generally, the amount of data for print jobs transmitted from a mobile terminal 101 is large, so it is necessary to use a communication method that enables high-speed communication for the communication of print jobs. For this reason, the MFP 151 receives print jobs via a communication unit 156 that enables communication at a higher speed than the short-range wireless communication unit 157. Note that printing using ink is just one example, and printing may also be performed using an electrophotographic method with toner. Furthermore, the MFP may be a cartridge type that uses cartridges, or an MFP that refills ink from an ink bottle into its ink tank.

[0034] Furthermore, the MFP151 may be equipped with optional memory devices such as an external HDD or SD card, and the information stored in the MFP151 may be stored in such memory.

[0035] The input interface 158 is an interface for receiving data input and operation instructions from the user when an operation unit 159, such as a physical button, is operated. The operation unit may also be a soft keyboard or soft buttons displayed on the display unit 161. In other words, the input interface 158 may also receive input from the user via the display unit 161.

[0036] The output interface 160 is an interface that controls the display unit 161 to display data and notify the status of the MFP 151.

[0037] The display unit 161 consists of LEDs (light-emitting diodes) and LCDs (liquid crystal displays), and is used to display data and notify the status of the MFP 151.

[0038] The USB interface 163 is an interface that controls USB connections via a USB cable. Specifically, the USB interface 163 is an interface for connecting to devices such as the MFP151 or external APs via USB and performing data communication.

[0039] Figure 3 is a block diagram showing an example of the functional configuration of AP131. AP131 has, for example, a wireless LAN control unit 301, a trigger frame control unit 302, a received frame analysis unit 303, a UI control unit 304, a storage unit 305, and a bandwidth distribution unit 306.

[0040] The wireless LAN control unit 301 performs control for sending and receiving wireless signals with other wireless LAN communication devices. The wireless LAN control unit 301 can be implemented, for example, by a program for controlling the baseband circuit, RF circuit and antenna for the wireless LAN. The wireless LAN control unit 301 performs wireless LAN communication control in accordance with the IEEE 802.11 standard series and performs wireless communication with STAs (equivalent to slave stations) that comply with the IEEE 802.11 standard series.

[0041] The Trigger frame control unit 302 controls the transmission of a Trigger frame to an STA that has successfully authenticated, via the Wireless LAN control unit 301. When the STA receives a Trigger frame, it transmits an Uplink (UL) frame as a response to that frame. When AP131 receives a UL frame via the Wireless LAN control unit 301, the Received Frame Analysis Unit 303 interprets the contents of the received UL frame. For example, if the received UL frame contains AC information, the Received Frame Analysis Unit 303 obtains the AC information through analysis and determines which AC data the STA that sent the UL frame possesses. "AC" is an acronym for Access Category.

[0042] The bandwidth allocation unit 306 determines, based on the information acquired by the received frame analysis unit 303, the width of the frequency band to be allocated for data transmission to each STA, the center frequency of the frequency band, and the time for allocating the frequency band. In other words, the bandwidth allocation unit 306 determines, for each STA, which frequency range of radio resources to allocate and at what timing. The trigger frame control unit 302 notifies each STA of the allocation determined by the bandwidth allocation unit 306 via a trigger frame and causes it to transmit UL frames according to that allocation.

[0043] The UI control unit 304 is implemented by a program that controls user interface hardware such as a touch panel or buttons for receiving operations on AP131 by a user (not shown) of AP131. The UI control unit 304 may also have functions for presenting information to the user, such as displaying images or outputting sound. The storage unit 305 is a storage function that may consist of ROM and RAM for storing programs and data on which AP131 operates.

[0044] Figure 7 is a diagram illustrating the subcarrier configuration. In IEEE 801.11ax, by allowing frequency bands smaller than 20 MHz to be allocated to STAs, a large number of STAs can simultaneously utilize radio resources. Such allocation of radio resources is performed using OFDMA (Orthogonal Frequency Division Multiple Access). In IEEE 802.11ax, for example, a 20 MHz bandwidth is divided into nine blocks, each containing 26 non-overlapping subcarriers (tones) on the frequency axis, and radio resources are allocated to terminals in block units. These allocated blocks are called Resource Units (RUs), and the size of the RU is determined according to the frequency bandwidth and the number of terminals receiving the radio resource allocation. The size of the RU is expressed in units of the number of tones; for example, 26, 52, 106, 242, 484, 996, and 2×996 are available, but for a 20 MHz bandwidth, values ​​of 242 or less are available. When allocating the entire 20 MHz bandwidth to a single terminal, a maximum of 242 tones can be allocated.

[0045] On the other hand, if, for example, nine terminals simultaneously use a 20MHz bandwidth, 26 tones are allocated to each terminal. In this way, by dividing the frequency band into the smallest allocation unit of 26 tones, nine terminals can communicate simultaneously using a 20MHz bandwidth. Similarly, when frequency bands of 40MHz, 80MHz, and 160MHz are used, up to 18, 37, and 74 terminals can communicate simultaneously, respectively.

[0046] Next, we will explain the basic flow of multi-user (MU) communication in UL using Figure 4. First, AP131 sends a Buffer Status Report Request (BSR Request) via the Trigger frame control unit 302 (S401). In this embodiment, AP131, MFP151, and mobile terminal 101 are capable of communication based on IEEE801.11ax. In this embodiment, mobile terminal 101 does not belong to the network formed by AP131.

[0047] Returning to Figure 4, each STA sends a Buffer Status Report (BSR) (S402). The BSR is used by each STA to notify the AP of its transmit buffer size. An example of the BSR frame structure is shown in Figure 5. The transmit buffer size of each STA is indicated in the Queue size subfield 503 contained in the QoS Control field 501. Alternatively, the transmit buffer size of each STA may be indicated by the Scaling Factor subfield 505, Queue Size High subfield 506, and Queue Size All subfield 507 within the Control Information subfield 504 of the HT Control field 502.

[0048] When AP131 receives a BSR from each STA, it sends a Trigger frame (S403) based on that information to prompt the transmission of UL data. At this time, AP131 determines the allocation of RUs in UL-OFDMA and the common communication time for all STAs based on the transmit buffer amount information contained in the BSR frame. Subsequently, AP131 sends a Trigger frame containing information about the RUs and the common data communication time for all STAs (hereinafter referred to as RU / communication time information). In other words, it sends a Trigger frame containing information related to OFDMA. Figure 6 shows the structure of the Trigger frame.

[0049] The Common Info field 601 contains information common to all STAs. The Length subfield 604 in the Common Info field 601 is set to the data communication time common to all STAs. If the Trigger Type subfield 603 is 0, the User Info field 602 is added. The Common Info field also contains other information. For example, CS (Carrier Sense) Required is included in the Common Info field, and it stores information indicating whether carrier sense should be performed. If information indicating that carrier sense should be performed is included, the STA that receives the trigger frame will perform carrier sense. On the other hand, if information indicating whether carrier sense should be performed is included, the STA that receives the trigger frame will not perform carrier sense. The STA is identified by the AID subfield 605 of the UserInfo field 602. In addition, the RU (Unit of Units) and tone size to be allocated to that STA are identified by the index value shown in the RU Allocation subfield 606. The tone size is a value that indicates the width of the frequency bandwidth that can be allocated to each STA. The MCS subfield 607 is set to MCS.

[0050] The AP reserves a communication channel to send a trigger frame. The AP then divides the reserved communication channel into multiple resource units and assigns each resource unit to a terminal.

[0051] When each STA receives a Trigger frame containing OFDMA-related information, it transmits a UL Data frame (S404) within the data volume range determined by the Length subfield 604 of the Trigger frame. If the frame contains information indicating that carrier sense must be performed, the STA performs carrier sense before executing S404. For example, MFP151 may transmit scanned data in S404. Other information regarding consumables (e.g., ink level, toner level, and paper level, at least one of these) may also be transmitted in S404. Alternatively, information indicating the status of MFP151 (e.g., paper jam error, cover open) may be transmitted.

[0052] When AP131 receives a PPDU from each STA, it sends a Multi Block Ack (Multi BA) as a confirmation of receipt (S405). Next, the operation of MFP151 will be explained using Figure 8. It is assumed that both infrastructure mode and P2P mode are enabled on MFP151 by user instruction. For example, both modes are enabled when the user enables infrastructure mode and WFD mode using the MFP151's control panel. Also, MFP151 operates as the master station (e.g., WFD group owner) in P2P communication. Note that P2P communication other than WFD mode may be performed. For example, soft AP mode may be executed.

[0053] Here, we assume that MFP151 receives a trigger frame from AP131 in S403. Note that if both infrastructure communication and P2P communication are enabled, MFP151 may refer to the communication channel used for infrastructure communication and configure the network as a master station to perform P2P communication on the same communication channel. Alternatively, if both infrastructure communication and P2P communication are enabled, MFP151 may refer to the communication channel used for infrastructure communication. Furthermore, MFP151 may configure the network as a master station to perform P2P communication on a communication channel different from the communication channel used for infrastructure communication. In other words, in Figure 8, MFP151 receives a trigger frame from external access point 131 in S403 while both infrastructure mode and P2P mode are enabled.

[0054] The MFP151, acting as the master station, transmits a Trigger frame (S801). Here, the MFP151 uses the Trigger frame described above (Figure 5) to divide one communication channel (e.g., 20MHz) into multiple resource units and assign each resource unit to an STA, including the mobile terminal 101. In other words, the RU Allocation 606 of the Trigger frame transmitted by the MFP151 contains information about the allocation of resource units. The number of slave station devices to which the MFP151 assigns resource units is the maximum number that can maintain a direct connection in parallel. For example, if the communication unit 156 can maintain a P2P wireless connection with a maximum of 3 slave station devices in parallel, the maximum number of slave station devices to which resource units are assigned is 3. In other words, the maximum number of devices to which resource units are assigned, as specified in the trigger frame of S801, is the same as the maximum number of slave stations that can be maintained in parallel in a direct connection. The mobile terminal 101 transmits data to the MFP151 in S802 (S802). Here, the mobile terminal 101 sends data using the resource unit allocated in the trigger frame. For example, the mobile terminal 101 sends a print job in S802. The mobile terminal 101 may also send a request to obtain the status of the MFP 151 or a request to obtain the remaining amount of consumables (ink, toner, or paper) in S802. Figure 9 illustrates an example of the operation screen 900 used for setting various modes in infrastructure mode or direct wireless communication. First, the user selects network setting 901 in Figure 9(A), which causes Figure 9(A) to transition to the screen in Figure 9(B). Figures 9(A) through (D) are displayed on the display unit 161.

[0055] Figure 9(B) shows the screen for configuring network settings. If the user selects infrastructure mode setting 904, Figure 9(C) will be displayed. If the user selects direct print setting 903, Figure 9(D) will be displayed.

[0056] Figure 9(C) shows the screen for performing configuration processing in infrastructure mode.

[0057] When the user checks checkbox 905, infrastructure mode is enabled. As a result, the MFP151 searches for nearby access points and displays a list of SSIDs in area 909. For example, the SSID of AP131 is displayed in area 909, and when the user selects the SSID of AP131 from area 909, a wireless connection in infrastructure mode is established between the MFP151 and AP131. To end communication in infrastructure mode, the user unchecks checkbox 905 and presses the OK button 910, which disables the MFP151's operation in infrastructure mode. For example, the wireless connection in infrastructure mode between the MFP151 and AP131 is disconnected.

[0058] In infrastructure mode communication, enabling or disabling OFDMA mode depends on the settings of AP131. That is, if OFDMA mode is enabled on AP131, MFP151 will perform infrastructure mode communication according to those settings.

[0059] On the other hand, if OFDMA mode is not enabled on AP131, MFP151 will perform infrastructure mode communication in OFDM mode according to its settings.

[0060] In OFDMA, a complex primary modulation scheme is required to keep the frequency bandwidth used for data transmission within a narrow range. Furthermore, a complex demodulation scheme is also necessary when demodulating communication data via OFDMA. Consequently, terminal equipment power consumption tends to increase.

[0061] On the other hand, when using OFDM wireless communication, a different method is used than the one described in Figure 8. That is, communication processing is performed by having a specific terminal occupy the entire bandwidth of the channel.

[0062] In OFDM, a specific terminal occupies the channel bandwidth, making it impossible to conduct wireless communication with multiple STAs simultaneously.

[0063] However, since OFDM does not require the segmented use of subchannels, primary modulation processing can be performed using a simple method. Therefore, when a terminal that receives a signal via OFDM communication demodulates the same signal, unlike OFDMA, complex and large-scale computational processing is not required, which reduces the power consumption of the terminal device.

[0064] As mentioned above, OFDMA and OFDM each have their own advantages and disadvantages. To make the most of their respective strengths, it is necessary to choose between these communication methods based on the usage environment.

[0065] In an environment where both AP131 and MFP151 are present, if OFDMA is performed on both AP131 and MFP151 (which acts as the master station), power consumption reduction cannot be achieved. Therefore, for example, if AP131 is performing OFDMA in infrastructure mode, MFP151 will not perform OFDMA in direct mode. This allows the benefits of OFDMA to be obtained in infrastructure mode, while power consumption in direct mode is reduced. Conversely, if AP131 is not performing OFDMA in infrastructure mode, MFP151 will perform OFDMA in direct mode. This reduces power consumption in infrastructure mode, while the benefits of OFDMA are obtained in direct mode. As a result, in an environment where both AP131 and MFP151 are present, it is possible to reduce power consumption while maintaining the convenience of communication.

[0066] Figure 9(D) is displayed when the user selects direct print setting 903 in Figure 9(B).

[0067] The MFP151 enables direct mode when the user checks checkbox 911 for direct print mode. Enabling direct mode causes the MFP151 to operate as a master station in P2P communication. In other words, if the P2P communication is WFD communication, the MFP151 operates as GO. Also, if the P2P communication is direct communication via software AP, the MFP151 operates as AP.

[0068] The OFDMA mode setting 912 is used to determine whether the communication unit 156 enables OFDMA mode in direct mode. If checkbox 913 is checked, direct communication is performed with OFDMA disabled. If checkbox 914 is checked, direct communication is performed with OFDMA enabled.

[0069] If checkbox 915 is selected here, the MFP151 checks whether OFDMA is enabled or disabled in infrastructure mode, and based on the result of that check, it decides whether to enable or disable PFDMA in direct mode.

[0070] Figure 10 illustrates the operation flow for enabling or disabling OFDMA in the direct mode of the MFP151. The flow shown in the figure is achieved by the CPU154 reading and executing each control program stored in the ROM152.

[0071] When the direct print setting operation is initiated, the CPU 154 accepts various setting operations related to the direct print setting in S1001. Specifically, the CPU 154 accepts various setting operations performed on the setting screen shown in Figure 9(D). In S1002, the CPU 154 determines whether the OK button 910 was selected or not. If the result of the determination in S1002 is true, the process in Figure 10 proceeds to step S1004 and beyond. If the result of the determination in step S1001 is false, the process proceeds to step S1003, where the CPU 154 determines whether the operation performed in S1001 was the selection of the cancel button or not. If the result of the determination in S1003 is false, the process returns to step S1001 and continues the setting operation. If the result of the determination in step S1003 is true, the setting operation according to the same flow is terminated.

[0072] In S1004, CPU 154 determines whether checkbox 915 is selected or not. If the result of the determination in S1004 is true, CPU 154 obtains the OFDMA mode status in infrastructure mode (S1006).

[0073] In step S1007, if it is determined that OFDMA is enabled in infrastructure mode, the CPU 154 operates OFDMA disabled in direct mode (S1009). The CPU 154 controls the communication unit 156 to operate as a master station in direct mode with OFDMA enabled when the MFP 151 is operated as a master station.

[0074] In S1007, if it is determined that OFDMA is not enabled in infrastructure mode, the CPU 154 enables OFDMA for direct mode (S1008). The CPU 154 controls the communication unit 156 so that the MFP 151 operates as a master station in direct mode with OFDMA enabled.

[0075] If the result of the determination in S1004 is false, the CPU 154 determines whether checkbox 914 is enabled (S1005). If it is determined in S1005 that checkbox 914 is selected, the CPU 154 executes S1008 as described above.

[0076] Furthermore, if it is determined in S1005 that checkbox 914 is not selected, CPU 154 executes S1009 as described above.

[0077] Through the above process, the MFP151 can perform communication processing in direct mode based on the settings shown in Figure 9(D).

[0078] Furthermore, even if OFDMA compliant with the IEEE 802.11 standard is enabled in infrastructure mode, the CPU 154 can control the MFP 151 so that OFDMA compliant with the IEEE 802.11 standard is not executed in direct mode wireless communication based on the activation of direct mode.

[0079] [Second Embodiment] In this embodiment, a process for enabling or disabling OFDMA in direct mode at a different timing than in the first embodiment will be described.

[0080] Figure 11 is a flowchart illustrating the process of enabling or disabling OFDMA in direct mode in this embodiment. The flow shown in the figure is realized by the CPU 154 reading and executing each control program stored in the ROM 152. Note that the flowchart in Figure 11 is initiated when a connection request for a direct connection is received from the terminal to the MFP 151.

[0081] In S1101, the CPU 154 checks the OFDMA mode settings in infrastructure mode and determines whether OFDMA is enabled or disabled (S1102). The CPU 154 can perform S1102 by referring to the RU Allocation of the Trigger frame shown in Figure 6 transmitted from the AP.

[0082] If it is determined in S1102 that OFDMA is disabled in infrastructure mode, the CPU 154 starts communication in direct mode with OFDMA enabled (S1103).

[0083] If it is determined in S1102 that OFDMA is enabled in infrastructure mode, the CPU 154 starts communication in direct mode with OFDMA disabled (S1104).

[0084] According to this embodiment, when a direct connection request is made to the MFP151, the status of the infrastructure mode is checked, enabling communication that reflects the latest status in infrastructure mode.

[0085] [Other embodiments] In the embodiments described above, the case in which the MFP151 enables direct mode after establishing a wireless connection in infrastructure mode was described, but this is not limited to that case. In other words, the MFP151 may enable direct mode before establishing a wireless connection in infrastructure mode. In that case, the MFP151 determines whether to enable or disable OFDMA in direct mode according to the setting of checkbox 913 or 914 in Figure 9(D).

[0086] In the embodiments described above, the enable or disable status of OFDMA in infrastructure mode was determined using trigger frames transmitted from AP131, but this is not limited to that. For example, MFP151 may receive information regarding the enable or disable status of OFDMA on AP131 via a wired connection with AP131.

[0087] Furthermore, the CPU 154 may control the MFP 151 so that OFDMA compliant with the IEEE 802.11 standard is not executed in direct mode wireless communication, regardless of the settings in the settings screen as shown in Figure 9. In other words, even if OFDMA compliant with the IEEE 802.11 standard is enabled in infrastructure mode, the CPU 154 may control the MFP 151 so that OFDMA compliant with the IEEE 802.11 standard is not executed in direct mode wireless communication based on the activation of direct mode.

[0088] This embodiment can also be implemented by supplying a program that implements one or more of the functions of the above-described embodiment to a system or device via a network or storage medium, and by having one or more processors in the computer of that system or device read and execute the program. It can also be implemented by a circuit (e.g., an ASIC) that implements one or more functions.

[0089] This embodiment includes the following configurations, methods, and programs.

[0090] (Composition 1) An image forming apparatus, A first setting means for enabling a first mode in which wireless communication is performed via an external access point outside the image forming apparatus, A second setting means for enabling a second mode in which wireless communication is performed without going through an external access point outside the image forming apparatus, A receiving means that, while the first mode is enabled, receives a first trigger frame containing OFDMA information compliant with the IEEE 802.11 standard from an external access point outside the image forming apparatus, A communication means that performs communication processing in the first mode by OFDMA compliant with the IEEE 802.11 standard based on information regarding the first trigger frame, Even if OFDMA compliant with the IEEE 802.11 standard is enabled in the first mode, control means for controlling the image forming apparatus so that OFDMA compliant with the IEEE 802.11 standard is not executed in the wireless communication of the second mode based on the activation of the second mode, Printing processing means that performs printing on paper based on a print job received via wireless communication via the first mode or wireless communication via the second mode. An image forming apparatus characterized by having the following features.

[0091] (Configuration 2) The image forming apparatus according to claim 1, further comprising a third setting means for receiving a setting on whether or not to perform OFDMA in the second mode of wireless communication via the operation panel of the image forming apparatus.

[0092] (Composition 3) The image forming apparatus according to claim 1 or 2, characterized in that the communication means transmits information indicating the remaining amount of consumables of the image forming apparatus or the status of the image forming apparatus based on OFDMA compliant with the IEEE 802.11 standard.

[0093] (Composition 4) The remaining amount of the aforementioned consumables is at least one of the remaining amount of ink, toner, and paper. The image forming apparatus according to claim 3, characterized in that the information indicating the state of the image forming apparatus is at least one of a paper jam error and a cover open.

[0094] (Composition 5) The image forming apparatus according to any one of claims 1 to 4, further comprising a disabling means for disabling OFDMA in the second mode of wireless communication based on the fact that OFDMA is enabled in the first mode of wireless communication.

[0095] (Composition 6) The image forming apparatus according to claim 5, characterized in that the disabling means disables OFDMA in the second mode of wireless communication based on information regarding OFDMA included in the trigger frame transmitted from the external access point.

[0096] (Composition 7) The system further includes a determination means for determining whether OFDMA is enabled in the first mode of wireless communication based on the activation of the second mode, The image forming apparatus according to claim 5 or 6, wherein if it is determined that OFDMA is enabled in the first mode of wireless communication, the enabling means disables OFDMA in the second mode of wireless communication.

[0097] (Composition 8) The system further includes determination means for determining whether OFDMA is enabled in the first mode of wireless communication based on the receipt of a connection request to the image forming apparatus in the second mode of wireless connection, The image forming apparatus according to any one of claims 5 to 7, wherein if OFDMA is determined to be enabled in the first mode of wireless communication, the disabling means disables OFDMA in the second mode of wireless communication.

[0098] (Composition 9) The image forming apparatus according to any one of claims 1 to 8, characterized in that when the second mode is activated, the image forming apparatus determines the communication channel used in the wireless communication of the second mode.

[0099] (Composition 10) The image forming apparatus according to any one of claims 1 to 9, characterized in that the first mode is an infrastructure mode and the second mode is a software AP mode. [Explanation of symbols]

[0100] 151 MFP

Claims

1. An image forming apparatus, A first setting means for enabling a first mode in which wireless communication is performed via an external access point outside the image forming apparatus, A second setting means for enabling a second mode in which wireless communication is performed without going through an external access point outside the image forming apparatus, A receiving means that, while the first mode is activated, receives a first trigger frame containing OFDMA information compliant with the IEEE 802.11 standard from an external access point outside the image forming apparatus, A communication means that performs communication processing in the first mode using OFDMA compliant with the IEEE 802.11 standard based on information regarding the first trigger frame, Even if OFDMA compliant with the IEEE 802.11 standard is enabled in the first mode, control means for controlling the image forming apparatus so that OFDMA compliant with the IEEE 802.11 standard is not executed in the wireless communication of the second mode based on the activation of the second mode, Printing processing means that performs printing on paper based on a print job received via wireless communication via the first mode or wireless communication via the second mode. An image forming apparatus characterized by having the following features.

2. The image forming apparatus according to claim 1, further comprising a third setting means for receiving a setting on whether or not to perform OFDMA in the second mode of wireless communication via the operation panel of the image forming apparatus.

3. The image forming apparatus according to claim 1, characterized in that the communication means transmits information indicating the remaining amount of consumables of the image forming apparatus or the status of the image forming apparatus based on OFDMA compliant with the IEEE 802.11 standard.

4. The remaining amount of the consumables is at least one of the remaining amount of ink, toner, and paper. The image forming apparatus according to claim 3, characterized in that the information indicating the state of the image forming apparatus is at least one of a paper jam error and a cover open.

5. The image forming apparatus according to claim 1, further comprising a disabling means for disabling OFDMA in the second mode of wireless communication based on the fact that OFDMA is enabled in the first mode of wireless communication.

6. The image forming apparatus according to claim 5, characterized in that the disabling means disables OFDMA in the second mode of wireless communication based on OFDMA information contained in the trigger frame transmitted from the external access point.

7. The system further includes a determination means for determining whether OFDMA is enabled in the first mode of wireless communication based on the activation of the second mode, The image forming apparatus according to claim 5, wherein, if it is determined that OFDMA is enabled in the first mode of wireless communication, the enabling means disables OFDMA in the second mode of wireless communication.

8. The system further includes determination means for determining whether OFDMA is enabled in the first mode of wireless communication based on the reception of a connection request to the image forming apparatus in the second mode of wireless connection, The image forming apparatus according to claim 5, wherein if OFDMA is determined to be enabled in the first mode of wireless communication, the deactivation means deactivates OFDMA in the second mode of wireless communication.

9. The image forming apparatus according to claim 1, characterized in that, when the second mode is activated, the image forming apparatus determines the communication channel used in the wireless communication of the second mode.

10. The image forming apparatus according to claim 1, characterized in that the first mode is an infrastructure mode and the second mode is a software AP mode.

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