Radio module and operation method thereof, radio terminal and operation method thereof

Abstract

A radio module and an operation method thereof, a radio terminal and an operation method thereof. A radio module (RM) for a radio terminal (T) is provided, wherein the radio module (RM) comprises: a transmitter (Tx) configured to transmit data on a first radio channel (RCH1) of a first radio communication network according to a first operation mode or on a second radio channel (RCH2) of a second radio communication network according to a second operation mode within a time period; and a controller (CTRL) configured to schedule selection of one of the operation modes of the transmitter (Tx), wherein the selection comprises switching at least one parameter of the transmitter (Tx) according to the selected operation mode.

Description

[0001] State-of-the-art technology

[0002] The present invention is directed to a radio module, a method of operating a radio module, a radio terminal and a method of operating a radio terminal.

[0003] In order to provide multiple connectivity to a radio terminal, the radio terminal has multiple radio modules configured to operate in a specific radio communication network. Summary of the invention

[0004] The radio module according to the disclosure herein, the method of operating a radio module according to the disclosure herein, the radio terminal according to the disclosure herein and the method of operating a radio terminal according to the disclosure herein solve the problems of the prior art. Advantages and further features can be found in the other claims and in the following exemplary description.

[0005] A first aspect is directed to a radio module for a radio terminal, wherein the radio module comprises: a transmitter configured to transmit data on a first radio channel of a first radio communication network according to a first operating mode or on a second radio channel of a second radio communication network according to a second operating mode within a time period; and a controller configured to schedule selection of one of the operating modes of the transmitter, wherein the selection comprises switching at least one parameter of the transmitter according to the selected operating mode.

[0006] Advantageously, the complexity of the transmitter is reduced, since only one radio channel of a radio communication system can be selected at the same time. Thus, only one entity for encoding and upsampling has to be integrated into the transmitter, which reduces the cost of the transmitter. On the other hand, the radio module provides multiple connectivity in a time-division multiplexing manner. The benefits of using multiple paths include an increase in reliability.

[0007] To increase reliability, appropriate multiple connectivity methods, such as packet replication, are deployed based on the characteristics of the communication path (e.g., received signal strength).

[0008] Thus, the radio module provides an increase in reliability by enabling the potential for multiple connectivity without requiring a second radio module which would increase the bill of materials of the final product.

[0009] An advantageous example is characterized in that the transmitter is configured to encapsulate a received first type MAC PDU into a first type PHY PDU, map the first type PHY PDU to be transmitted on at least one first subcarrier, and subsequently up-convert to a first radio frequency higher than the at least one first subcarrier; and in that the transmitter is configured to encapsulate a received second type MAC PDU into a second type PHY PDU, map the second type PHY PDU to be transmitted on at least one second subcarrier, and subsequently up-convert to a second radio frequency higher than the at least one second subcarrier.

[0010] Hence, the transmitter provides an advantageous interface which can be fed by different communication stacks.In particular, the communication stack providing the MAC PDU can be provided as software.

[0011] The first subcarrier and the first radio frequency represent parameters of the transmitter according to a first operating mode. The second subcarrier and the second radio frequency represent parameters of the transmitter according to a second operating mode.

[0012] An advantageous example is characterized in that the controller is configured to switch the at least one parameter according to the first radio channel or the second radio channel depending on a predetermined switching pattern, the predetermined switching pattern comprising a fixed access period of the transmitter.

[0013] By providing a predetermined switching pattern, a transmission ratio for both radio communication networks is improved.

[0014] An advantageous example is characterized in that the controller is configured to switch the at least one parameter according to the first radio channel or the second radio channel depending on a received end-of-transmission indicator indicating an end of transmission via the second radio channel or the first radio channel.

[0015] Advantageously, the controller grants the transmitter access for radio transmission if another radio channel is not in use by said radio module.

[0016] An advantageous example is characterized in that the radio module comprises: a receiver configured to receive at least one authorization, the at least one authorization authorizing the transmitter to transmit data via the first radio channel or the second radio channel; and the controller is configured to switch to the first operating mode or the second operating mode depending on the received authorization.

[0017] Advantageously, if the first and / or second radio communication system has an authorization procedure, for example operated via an access point, a received authorization causes the controller to switch the operating mode to the radio channel for which said authorization was received.

[0018] An advantageous example is characterized in that the radio module comprises a controller configured to operate the transmitter to transmit a first scheduling request towards a scheduling entity of the first radio communications network during the first operation mode.

[0019] Advantageously, the controller triggers the grant and adapts the schedule of the operating mode selection according to the received grant.Thus, the radio module provides a synchronization technique for the first radio communications network.

[0020] An advantageous example is characterized in that the radio module comprises a controller configured to operate the transmitter to transmit a second scheduling request towards a scheduling entity of the second radio communications network during the second operation mode.

[0021] Advantageously, the controller adapts the operation of the transmitter in dependence on scheduling grants originating from at least two different radio communication networks.The scheduling requests are determined by the controller in order to trigger grants directed to granted radio resources that do not interfere in time.

[0022] An advantageous example is characterized in that the radio module comprises a controller which is configured to maintain the present operating mode or to switch to the first operating mode or the second operating mode depending on the transmission priority of the data.

[0023] By incorporating the transmission priority into the decision for scheduling the operation mode selection, other influencing parameters can be overridden. Advantageously, this guarantees the transmission of certain high priority tagged data.

[0024] An advantageous example is characterized in that the radio module comprises: a / the receiver configured to sense the first radio channel as idle or busy; a controller configured to switch the transmitter from the first operation mode to the second operation mode if the first radio channel is sensed to be idle, and to switch the transmitter from the second operation mode to the first operation mode if the first radio channel is sensed to be busy.

[0025] Hence, a mode priority is provided, wherein transmission via the first radio channel is preferred over transmission via the second radio channel.Data is transmitted via the second radio channel only when the first radio channel is sensed to be idle.

[0026] A second aspect of the description is directed to a method for operating a radio module, wherein the method comprises: transmitting data on a first radio channel of a first radio communication network according to a first operating mode or on a second radio channel of a second radio communication network according to a second operating mode within a time period; and scheduling selection of one of the operating modes of the transmitter, wherein the selection comprises switching at least one parameter of the transmitter according to the selected operating mode.

[0027] A third aspect is directed to a radio terminal for use in at least two radio communication networks, wherein the radio terminal comprises a radio module according to the first aspect.

[0028] A favorable example is characterized in that the radio terminal includes at least one processor, at least one memory having computer program code, and at least one antenna, and the computer program code is configured to interact with the at least one processor, the at least one antenna and the at least one radio module so that the radio terminal determines one / the first type of MAC PDU depending on a first payload and provides the first type of MAC PDU to a transmitter; and determines one / the second type of MAC PDU depending on a second payload and provides the second type of MAC PDU to the transmitter.

[0029] Thus, an advantageous interface is provided that allows multiple software stacks for determining and providing a MAC PDU to a transmitter.

[0030] A fourth aspect is directed to a method of operating a radio terminal according to the third aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 schematically depicts a radio module of a radio terminal;

[0032] Figure 2 schematically depicts an example of a radio terminal; and

[0033] Figures 3 to 6 Each schematically depicts a sequence diagram.

[0034] Figure 1 Schematically depicted is a radio module RM of a radio terminal T. The radio module RM is adapted to transmit on a plurality of radio channels RCH1, RCH2 of different radio communication networks. In the example shown, a first network entity N1 communicates with the radio terminal T via a first radio channel RCH1. A second network entity N2 communicates with the radio terminal via a second radio channel RCH2. Both radio channels RCH1 and RCH2 belong to different radio communication networks and differ at least in radio frequency and further differ in at least one of the following: modulation scheme, coding scheme, subcarrier frequency and transmission time interval.

[0035] Access to the radio channels RCH1 and RCH2 is handled in a distributed or centrally managed manner. Thus, the example of a system comprises network entities N1, N2 with the same or different media access schemes.

[0036] The radio module RM comprises a transmitter Tx and a controller CTRL. The transmitter Tx is configured to transmit the provided data on a first radio channel RCH1 of a first radio communication network according to a first operating mode or on a second radio channel RCH2 of a second radio communication network according to a second operating mode within a time period. The provided data is mapped to subcarriers, then up-converted into corresponding radio signals and provided by the transmitter Tx to at least one antenna A for transmission via the radio signals of the first radio channel or the second radio channel RCH1, RCH2.

[0037] The data to be transmitted is provided to the transmitter Tx. For example, the MAC layer tasks and higher layer tasks are processed in software. Therefore, the data to be transmitted is handed over to the transmitter Tx at the egress part of the MAC layer.

[0038] The controller CTRL is configured to schedule a selection of one of the operating modes of the transmitter Tx, wherein the selection comprises switching at least one parameter of the transmitter Tx depending on the selected operating mode.

[0039] The at least one parameter of the transmitter Tx for operating the radio channels RCH1 and RCH2 of the respective radio communication system comprises one of the following:

[0040] - Modulation scheme,

[0041] - Coding scheme,

[0042] - radio frequencies,

[0043] - subcarrier frequency,

[0044] - The transmission interval.

[0045] The selection of one of the operation modes comprises a switching operation including an adaptation of at least one parameter of the transmitter Tx. The selection is associated with a switching delay.

[0046] Examples of select schedules include:

[0047] - Figure 3 The fixed-time schedule exemplified in

[0048] -based on Figure 4 Flexible timing scheduling of the transmission needs of the associated communication stack illustrated in

[0049] -based on Figure 5 Flexible timing scheduling of external radio access scheduling as exemplified in;

[0050] -based on Figure 5 Flexible timing scheduling of transmission priorities as exemplified in ; and

[0051] -based on Figure 6 Flexible timing scheduling of channel sensing illustrated in FIG.

[0052] Of course, the provided scheduling methods of operating mode selection may be changed during operation of the radio module RM. Furthermore, combinations of the provided methods are possible.

[0053] The resources of the transmitter Tx (i.e. the RF chain and baseband processing) are divided into time slots, and the controller CTRL schedules access to these resources between two or more independent communication protocol stacks. The physical layer resources are independently configured for each time slot via at least one parameter, wherein each time slot is thus bound to one of the operating modes. Due to the time multiplexed use of the resources of the transmitter Tx, the access scheme provided for the transmitter Tx increases the transmission delay over multiple paths to a certain extent.

[0054] The transmitter Tx is connected to at least one antenna A in order to transmit radio signals. The radio signals switch radio frequencies in a time division manner according to the access scheme provided for the radio module RM. Therefore, the radio signals transmitted by the radio module have different frequencies and are independent of each other, i.e., use different source addresses, for example.

[0055] By adjusting the length and start of the time slot, the access scheme is optimized for various conditions in different frequency bands. For example, exclusive access to the spectrum using a central coordination unit in the IMT-spectrum or in the 3.7-3.8 GHz band, or shared access to the spectrum using distributed coordination based on CSMA-CA in the 2.4 and 5 GHz bands. In this example, the terminal T is connected to two access points in the form of network entities N1 and N2, which work at 5 GHz and 3.7 GHz respectively.

[0056] Figure 2 An example of a radio terminal T is schematically depicted. The radio terminal T comprises a radio module RM and a processor P. A memory M with a computer program code is provided. The computer program code, if executed on the processor P, causes the radio terminal T to execute an application APP, a first communication stack St1 and a second communication stack St2. The application APP provides data to be transmitted via at least one of the radio channels RCH1, RCH2 to a plurality of queues qx.

[0057] In the example shown, the radio terminal T comprises a receiver Rx connected to at least one antenna A. The receiver Rx is configured to sense the occupancy of at least one of the radio channels RCH1 and RCH2 and / or to provide data, which is transmitted to the controller CTRL via at least one of the radio channels RCH1 and RCH2. The receiver Rx as an occupancy sensing device may comprise a less complex receiver chain which does not fully decode the received data but only senses the occupancy.

[0058] In another example, the receiver Rx is configured to receive data on the first radio channel RCH1 of the first radio communication network or on the second radio channel RCH2 of the second radio communication network according to the first operating mode within a time period. The operating mode is switched via a switching signal sw. According to this example, both the transmitter Tx and the receiver Rx are bound to the currently set radio frequency. Advantageously, only one radio module is required because only the radio frequency on which the receiver RX is currently listening is used. If the corresponding radio channels RCH1, RCH2 are occupied, the radio terminal T switches to another radio channel RCH2, RCH1 and attempts to transmit there. In the case of two radio networks, the receiver Rx switches back and forth between frequencies, standards, etc. to receive data and set a sleep time for another radio network, where the receiver Rx does not receive. During this sleep time, other network entities temporarily store packets for the receiver Rx until the receiver Rx returns to receiving on the corresponding frequency.

[0059] In the example shown, the controller CTRL is provided as hardware like the transmitter Tx.In an alternative example, the controller CTRL is provided as a software function provided as a computer program code running on a dedicated processor or on a processor P, wherein the transmitter Tx is implemented as hardware.

[0060] The first communication stack St1 receives a first payload p1 from an application APP at its ingress queue iq1. The protocol processing unit pp1 takes the first payload p1 from the ingress queue iq1, processes the payload p1 according to at least one first communication protocol assigned, and determines a corresponding first type MAC PDU (1) provided in the egress queue eq1.

[0061] The transmitter Tx comprises a PHY unit 200 configured to encapsulate a first type MAC PDU (1) into a first type PHY PDU (1). The first type PHY PDU (1) enters a queue 202. A radio unit 204 maps the first type PHY PDU (1) to be transmitted on at least one first subcarrier and then up-converts to a first radio frequency higher than the at least one first subcarrier.

[0062] According to an example, the radio unit 204 implements at least two different radio standards in the PHY and switches between these radio standards depending on the switching signal sw, thus maintaining time multiplexing between the two radio systems.

[0063] According to another example, the radio unit 204 implements at least two similar radio standards in the PHY interface and switches between the similar radio standards depending on the switching signal sw, wherein the difference between the two similar radio standards depends on the radio frequency and the subcarrier frequency.

[0064] The second communication stack St2 receives a second payload p2 from the application APP at its ingress queue iq2. The protocol processing unit pp2 takes the second payload p2 from the ingress queue iq2, processes the payload p2 according to at least one second communication protocol assigned, and determines a corresponding second type MAC PDU (2) provided in the egress queue eq2.

[0065] The PHY unit 200 is configured to encapsulate the second type MAC PDU (2) into the second type PHY PDU (2). The second type PHY PDU (2) enters the queue 202. The radio unit 204 maps the second type PHY PDU (2) to be transmitted on at least one second subcarrier and then up-converts to a second radio frequency higher than the at least one second subcarrier.

[0066] The controller CTRL schedules access to the transmitter Tx for at least two communication stacks St1 and St2. The scheduling decision of the control CTRL includes transmitting a switching signal sw to the transmitter Tx. In an example, the radio unit 204 receives the switching signal sw. After receiving the switching signal 204, the radio unit 204 transmits the PHY PDU residing in the queue 202 to clear the queue 202. Then the radio unit 204 changes at least one parameter to change the operation mode of the transmitter Tx. In other words, the radio unit 204 changes its transmission mode to transmit radio signals via the radio channels RCH1, RCH2 that were not selected before receiving the switching signal sw. When the radio unit 204 has successfully changed its operation mode, the radio unit 204 transmits another switching signal sw2 to the PHY unit 200 to switch to the selected operation mode. In other words, after receiving the other switching signal sw2, the PHY unit 200 will switch to receiving the MAC PDU from another one of the egress queues eq2, eq1 of the corresponding communication stacks St2, St1.

[0067] Therefore, the controller CTRL controls at least the radio frequency setting of the radio unit 204 and issues a switching signal sw to change from a first radio frequency to a second radio frequency. The switching signal sw can be triggered based on a specific switching cycle, the end of transmission of the communication stack that is transmitting at the current radio frequency, or based on other inputs, such as scheduling authorization from an external central coordinator such as a base station or access point. Before issuing the switching signal sw, the currently operating communication stack St1 is notified of the upcoming frequency switch so that it can suspend its processing, run timers related to scheduling or media access, such as the backoff process in CMSA / CA. In another example, the communication stack St1 or the controller CTRL monitors the priority of the incoming payload p1 of the communication stack St1 and requests access to the transmitter Tx.

[0068] After the switching period required for the RF hardware of the radio module 204 to set up the new radio frequency, the activated communication stack St1 , St2 continues with the data transfer process suspended until the controller CTRL signals the next switch via the switching signal sw.

[0069] In the setting of strict quality of service requirements required by the application APP, the controller CTRL will use these requirements (such as the delay deadline) as input and adapt the switching between the radio systems accordingly. If both radio communication networks are managed in a distributed manner and, for example, IEEE 802.11DCF is used as input, the backoff values ​​of the two radio communication networks are used to determine the most promising switching routine via the controller CTRL to meet the quality of service requirements. In the case where the first radio communication network provides a much higher backoff than the second radio communication network, the controller CTRL allocates the next time slot for transmission via the first radio communication network and lets the second communication stack St2 count down its backoff value, while the first communication stack St2 uses the time slot for transmission via the transmitter Tx.

[0070] Figure 3 A sequence diagram of a method of operating a terminal T is schematically depicted.

[0071] The controller CTRL is configured to switch at least one parameter according to the first or second radio channel RCH1 , RCH2 depending on a predetermined switching pattern, the predetermined switching pattern comprising a fixed access period aP of the transmitter Tx.

[0072] According to step 302, the application APP determines the payloads p1 and p2 and submits these to the corresponding communication stacks St1, St2. At time t0_3, the second communication stack St2 starts accessing the transmitter Tx during the access period aP(2). During the access period aP(2), the second communication stack St2 has access to the transmitter Tx. During the access period aP(2), the controller CTRL schedules the selection of the operating mode OP of the transmitter Tx via step 304. Step 304 includes notifying the first communication stack St1 that it starts having access to use the transmitter Tx at time t2_3. Step 304 includes that the second communication stack St2 must end its access to the transmitter Tx at time t1_3.

[0073] During the switching period swP, the controller CTRL determines a switching signal sw in step 306. According to step 308, upon receiving the switching signal sw, the transmitter Tx changes its current second operation mode to the first operation mode in order to use the first radio channel instead of the second radio channel.

[0074] During the access period aP(1), the controller initiates a further switching operation in step 314. The first communication stack St1 is notified to stop access to the transmitter Tx at time t3_3. The second communication stack St2 is notified to start access to the transmitter Tx at time t4_3.

[0075] During the following switching period swP, the controller CTRL determines a switching signal sw in step 316. According to step 318, upon receiving the switching signal sw, the transmitter Tx changes its current first operation mode to a second operation mode in order to use the second radio channel instead of the first radio channel in the access period aP(2).

[0076] According to this example, multiple connectivity is achieved by using only one modem in the sense of the radio module RM. The time slot structure shown includes fixed access periods for each communication stack St1 and St2. For example, between the frequency bands of 2.4 GHz and 5 GHz, switching occurs every 2 ms. The available time includes the access periods aP(1) and aP(2) of the corresponding time slots minus the RF switching period swP.

[0077] The first communication stack 1 compromises all required layers from the MAC layer upwards and is working as usual, and transmits in the 2.4 GHz frequency band. The first communication stack St1 has its own MAC address, IP address, etc. The ongoing transmission must be ended before switching to the second operating mode. At the end of the access period aP(1), the current state of the communication stack St1, such as backoff timer, session timer, etc., is paused and continued in the next access period aP(1). During the access period aP(2), the second communication stack St2 accesses the transmitter Tx to transmit in the 5 GHz frequency band based on the state of the second communication stack St2. The communication stacks St1 and St2 can be used, for example, by a multi-connectivity engine at an application APP to transmit duplicate data through two communication paths of different radio communication networks.

[0078] Figure 4 Schematically depicted is a sequence diagram of a method of operating a terminal T. The controller CTRL is configured to switch at least one parameter according to the first or second radio channel RCH1, RCH2 depending on a received end of transmission indicator eot2, eot1 indicating an end of transmission via the second or first radio channel RCH2, RCH1.

[0079] According to step 402, the application APP determines the payloads p1 and p2 and submits these to the corresponding communication stacks St1, St2. At time t0_4, the second communication stack St2 begins access to the transmitter Tx during the access period aP(2). During the access period aP(2), the second communication stack St2 determines in step 404 that the communication stack St2 will end its access to the transmitter Tx at time t1_4. During the switching period swP, the controller CTRL schedules the selection of the first operating mode of the transmitter Tx via step 406. Step 406 includes notifying the first communication stack St1 that it has access to the transmitter Tx to use the transmitter Tx starting at time t2_4. Step 406 includes notifying the transmitter Tx via the switching signal sw to switch the operating mode of the transmitter Tx to the first operating mode in step 408.

[0080] At time t2_4, the first communication stack St1 starts access to the transmitter Tx during the access period aP(1). During the access period aP(1), the first communication stack St1 determines in step 414 that the communication stack St1 will end its access to the transmitter Tx at time t3_4. During the switching period swP, the controller CTRL schedules the selection of the second operating mode of the transmitter Tx via step 416. Step 416 includes notifying the second communication stack St2 that it starts to have access to the transmitter Tx at time t4_4 to use the transmitter Tx. Step 416 includes notifying the transmitter Tx via the switching signal sw to switch the operating mode of the transmitter Tx to the second operating mode in step 418.

[0081] Figure 5 A sequence diagram of a method of operating a terminal T is schematically depicted.

[0082] The receiver Rx is configured to receive at least one grant g1, g2 authorizing the transmitter Tx to transmit data via the first or second radio channel RCH1, RCH1. The controller CTRL is configured to switch to the first or second operation mode depending on the received grant g1, g2.

[0083] The controller CTRL is configured to operate the transmitter Tx to transmit a first scheduling request r1 towards a scheduling entity N1 of the first radio communications network during the first operation mode.

[0084] The controller CTRL is configured to operate the transmitter Tx to transmit a second scheduling request r2 towards the scheduling entity N2 of the second radio communications network during the second operation mode.

[0085] According to step 502, the application APP determines the payloads p1 and p2 and submits these to the corresponding communication stacks St1, St2. At time t0_5, the second communication stack St2 starts accessing the transmitter Tx during the access period aP(2). During the access period aP(2), the second communication stack St2 has access to the transmitter Tx. In an example not shown, the second communication stack St2 can initiate the transmission of the second payload p2 to the network node N2 of the second radio communication network. The controller CTRL schedules in step 504: the second communication stack St2 ends its access to the transmitter at time t1_5, and the first communication stack St1 starts accessing the transmitter Tx at time t2_5.

[0086] During the following switching period swP, the controller CTRL initiates a switch of the second operation mode to the first operation mode of the transmitter Tx in step 508. In step 510, the transmitter switches to the first operation mode depending on the received switching signal sw.

[0087] During the access period aP(2), in step 506, the controller CTRL or the second communication stack St2 (not shown) causes the transmitter Tx to transmit a scheduling request r2 towards a network node N2 configured as a scheduling entity for the second radio communication network. The network node N2 determines a grant g2 in step 511, which is received by the receiver Rx of the radio module RM. The receiver Rx passes the grant g2 to the controller CTRL. In step 512, the controller CTRL informs the first communication stack St1 that it must end access to the transmitter until time t3_5, depending on the grant g2.

[0088] In step 512, the controller CTRL informs the second communication stack St2 that it will get access to the transmitter Tx starting at time t4_5, depending on the grant g2. The grant g2 indicates the radio resources of the second radio channel in the access period aP(2) between t4_5 and t5_5.

[0089] The controller CRTL starts its switching process at time t3_5. In step 514, the controller CRTL asserts a switching signal sw such that the transmitter Tx changes its operation mode to the second operation mode in step 516. According to the received grant g2, the second communication stack St2 is able to transmit payload data p2 via the granted radio resources of the second radio channel.

[0090] During the access period aP(2) between t2_5 and t3_5, the controller CTRL or (not shown) the first communication stack St1 initiates in step 520 a grant request r1 to be sent via the transmitter Tx towards the network node N1 acting as a scheduling entity for the first radio communication network. The network node N1 schedules radio resources of the first radio channel and in step 522 determines the grant g1 received by the receiver Rx and hands it over to the controller CTRL.

[0091] According to step 524, the controller CTRL informs the first communication stack St1 that it can start accessing the transmitter Tx at time t6_5 and informs the second communication stack St2 that its access to the transmitter Tx will end at time t5_5. The following steps 508 and 510 depend on the determined time t5_5.

[0092] The method provided aligns the switching period swP with the access periods aP(1) and aP(2) based on scheduling decisions from centrally coordinated communications in the first and second radio communication networks. In this case, the two radio communication networks are centrally coordinated. For example, in the case where both systems are scheduled as semi-continuous, the controller CTRL will influence the network nodes N1 and N2 to schedule the corresponding radio resources so that the scheduled radio resources of the two radio communication networks are scheduled without overlapping in time. By doing so, the switching period swP and the access periods aP(1) and aP(2) are adapted to the corresponding resource allocations, and no radio resources according to the authorizations g1 and g2 are missed by the radio terminal T.

[0093] Another example of switching scheduling is given below. In a system in which IEEE 802.11 is used in HCCA mode, a contention-free period (CFP) and a contention period (CP) are periodically switched, during which the HCCA controller CTRL manages channel access, and during which the channel is used by other nodes in DCF mode. HCCA is a centrally coordinated communication scheme in which a hybrid coordinator controls access to the media. If both radio communication networks use the HCCA mode, the controller CTRL will influence the network nodes N1 and N2 so that the CFP periods of the two radio systems do not overlap in time, and schedule the switching between the two radio communication networks accordingly.

[0094] If only one radio communication network uses HCCA and the other is using a distributed scheme, such as 802.11 DCF, the controller CTRL will schedule the switch according to the CFP cycle of the HCCA radio communication network and let the other communication stack do its best effort to transmit in the remaining time slots.

[0095] According to a further example, not shown in its entirety, the controller CTRL is configured to maintain the present operating mode or to switch to the first operating mode or the second operating mode depending on the transmission priority of the data. The controller CTRL compares the transmission priorities of the MAC PDUs in the egress queues of the different communication stacks St1 and St2. Thus, if in step 512 the controller CTRL also considers the higher transmission priority of the MAC PDUs of the first communication stack St1, the controller CTRL will ignore the grant g2 in step 512 and keep the first operating mode of the transmitter Tx active.

[0096] In addition, in a hybrid setting, in which the media access of the first radio communication network is centrally coordinated and the media access of the second radio communication network is managed in a distributed manner, the switching times can be adjusted so that they give priority to the resources of the first radio communication network. By doing so, at least the path on the first radio communication network can predictably transmit packets, while the second radio communication network only transmits on a best effort basis. However, the access period for the first communication stack St1 is kept to a minimum, which leaves more time for the second communication stack St2 to access the channel.

[0097] Figure 6 A sequence diagram is schematically depicted.The receiver Rx is configured to sense a first radio channel as being idle or busy.

[0098] The controller CTRL is configured to switch the transmitter Tx from the first operation mode to the second operation mode if the first radio channel RCH1 is sensed to be idle, and to switch the transmitter Tx from the second operation mode to the first operation mode if the first radio channel RCH1 is sensed to be busy.

[0099] According to step 602, the application APP determines the payloads p1 and p2 and submits these to the corresponding communication stacks St1, St2. At time t0_6, the controller CTRL informs the second communication stack St2 in step 604 that it has access to the transmitter Tx starting at time t1_6. Depending on the received switching signal sw, the transmitter Tx changes its operating state to the second operating state in step 606.

[0100] The receiver Rx senses that the first radio channel RCH1 is busy at time t2_6 and starts changing the operating state of the transmitter Tx to the first operating state in step 608. The transmitter Tx changes its operating state to the first operating state in step 610. The second communication stack St2 is notified to stop access to the transmitter Tx. The first communication stack St2 is notified to start providing access to the transmitter Tx at time t3_6.

[0101] As soon as the receiver Rx senses that the first channel RCH1 is idle, the controller CTRL initiates in step 612 a change in the operating state of the transmitter Tx to a second operating state in step 614 .

[0102] The second communication stack St2 starts accessing the transmitter Tx during the access period aP(2). During the access period aP(2), the second communication stack St2 has access to the transmitter Tx. In an example not shown, the second communication stack St2 can initiate the transmission of the second payload p2 to the network node N2 of the second radio communication network. The controller CTRL schedules in step 504 that the second communication stack St2 ends its access to the transmitter at time t1_5 and the first communication stack St1 starts accessing the transmitter Tx at time t2_5.

[0103] According to this exemplary setting, the transmission occurs according to an uncoordinated scheme in which the radio terminals T in 3.7 GHz act as primary users and those in the Wi-Fi band act as secondary users. Therefore, a Wi-Fi user can only start transmitting when there is no 3.7 GHz transmission. This means that the controller CTRL monitors at least the first radio channel RCH1 in order to detect the presence of potential transmissions. As long as the transmission in 3.7 GHz / first radio channel RCH1 is suspended, the Wi-Fi user will take advantage of this opportunity to transmit an unknown amount of data (burst) depending on the allocated time, and must vacate as soon as the 3.7 GHz transmission follows, which means that the first radio channel RCH1 is sensed to be busy. In other words, the Wi-Fi user takes advantage of the idle period to transmit data on the second radio channel RCH2. This setting takes into account conventional Wi-Fi users using CSMA / CA and users in a tuned Wi-Fi system without a channel access mechanism.

Claims

1. A radio module (RM) for a radio terminal (T), wherein the radio module (RM) comprises: a transmitter (Tx) configured to transmit data on a first radio channel (RCH1) of a first radio communications network according to a first operating mode or on a second radio channel (RCH2) of a second radio communications network according to a second operating mode within a time period; and a controller (CTRL) configured to schedule selection of one of the operating modes of a transmitter (Tx), wherein the selection comprises switching at least one parameter of the transmitter (Tx) according to the selected operating mode, wherein the radio module (RM) comprises: a receiver (Rx) configured to sense the first radio channel or the second radio channel (RCH1; RCH2) as idle or busy; A controller (CTRL) configured to switch the transmitter (Tx) from the first operation mode to the second operation mode if the first radio channel (RCH1) is sensed to be busy, and to switch the transmitter (Tx) from the second operation mode to the first operation mode if the second radio channel (RCH2) is sensed to be busy.

2. The radio module (RM) according to claim 1, in, The transmitter (Tx) is configured to encapsulate the received first type MAC PDU into a first type PHY PDU, map the first type PHY PDU to be transmitted on at least one first subcarrier, and then up-convert to a first radio frequency higher than the at least one first subcarrier; Wherein the transmitter (Tx) is configured to encapsulate the received second type MAC PDU into a second type PHY PDU, map the second type PHY PDU to be transmitted on at least one second subcarrier, and then up-convert to a second radio frequency higher than the at least one second subcarrier.

3. A radio module (RM) according to one of the preceding claims 1 - 2, wherein the controller (CTRL) is configured to switch the at least one parameter according to the first radio channel or the second radio channel (RCH1; RCH2) depending on a predetermined switching pattern, the predetermined switching pattern comprising a fixed access period (ap) of the transmitter (Tx).

4. Radio module (RM) according to one of the preceding claims 1 - 2, The controller (CTRL) is configured to switch the at least one parameter according to the first radio channel or the second radio channel (RCH1; RCH2) depending on a received end-of-transmission indicator (eot2; eot1), the end-of-transmission indicator (eot2; eot1) indicating the end of transmission via the second radio channel or the first radio channel (RCH2; RCH1).

5. The radio module (RM) according to one of the preceding claims 1 - 2, wherein the radio module (RM) comprises: a receiver (Rx) configured to receive at least one grant (g1; g2) authorizing a transmitter (Tx) to transmit data via the first radio channel or the second radio channel (RCH1; RCH2); as well as A controller (CTRL) configured to switch to a first operating mode or a second operating mode depending on a received authorization (g1; g2).

6. The radio module (RM) according to claim 5, wherein the radio module (RM) comprises: A controller (CTRL) is configured to operate a transmitter (Tx) to transmit a first scheduling request (r1) towards a scheduling entity (N1) of a first radio communications network during a first operation mode.

7. The radio module (RM) according to claim 5, wherein the radio module (RM) comprises: A controller (CTRL) is configured to operate the transmitter (Tx) to transmit a second scheduling request (r2) towards a scheduling entity (N2) of a second radio communications network during a second operation mode.

8. The radio module (RM) according to one of the preceding claims 1 - 2, wherein the radio module (RM) comprises: The controller is configured to maintain the current operation mode or switch to the first operation mode or the second operation mode depending on the transmission priority (p1; p2) of the data.

9. The radio module (RM) according to one of the preceding claims 1 - 2, wherein the radio module (RM) comprises: A receiver (Rx) is configured to receive data on a first radio channel (RCH1) of a first radio communication network according to a first operating mode or on a second radio channel (RCH2) of a second radio communication network according to a second operating mode within a time period.

10. A method of operating a radio module (RM), wherein the method comprises: transmitting data on a first radio channel (RCH1) of a first radio communications network according to a first operating mode or on a second radio channel (RCH2) of a second radio communications network according to a second operating mode within a time period; and scheduling a selection of one of the operating modes of the transmitter (Tx), wherein the selection comprises switching at least one parameter of the transmitter (Tx) according to the selected operating mode, sensing that the first radio channel or the second radio channel (RCH1; RCH2) is idle or busy; as well as The transmitter (Tx) is switched from the first operation mode to the second operation mode if the first radio channel (RCH1) is sensed to be busy, and the transmitter (Tx) is switched from the second operation mode to the first operation mode if the second radio channel (RCH2) is sensed to be busy.

11. Method according to claim 10, wherein the method is adapted to operate a radio module (RM) according to one of claims 2 to 9.

12. A radio terminal (T) for at least two radio communication networks, wherein the radio terminal (T) comprises a radio module (RM) according to one of claims 1 to 9.

13. The radio terminal (T) according to claim 12, wherein the radio terminal (T) comprises at least one processor, at least one memory with computer program code, and at least one antenna, the computer program code being configured to interact with the at least one processor, the at least one antenna and the at least one radio module (RM) so that the radio terminal (T) determining a first type MAC PDU depending on the first payload, and providing the first type MAC PDU to a transmitter (Tx); and A second type MAC PDU is determined depending on the second payload, and the second type MAC PDU is provided to the transmitter (Tx).

14. A method of operating a radio terminal (T) according to claim 12 or 13.

Images