RU2445734C1 - Method of transmitting data stream in wireless communication system - Google Patents

Abstract

FIELD: information technology.

SUBSTANCE: given problem is solved by using a method of transmitting a data stream in a mobile device in a wireless communication system, where two switching methods are used separately or together in accordance with the value of the data stream, which enables rational use of system resources overall. In case of isolated communication requests, when overall traffic is minimal, the mobile device either executes a switching mode in a dedicated channel switched connection, thereby transmitting information of the previous mobile device to the next, or is in receiving mode. With increase in the number of communication requests and data stream, a large number of mobile devices in receiving mode is successively included into the structure of dedicated channel switched connections. The moment the last mobile device, which is in standby mode, is included in the channel switched connection structure, the next communication request leads to that a requirement to set up a connection for switching another channel is sent to the mobile device switching the dedicated channel. The mobile device switches to packet switching mode, while receiving the packets, recording them into buffer memory and transmitting them according to a "first in first out" rule.

EFFECT: high efficiency of using radio resources of a communication system overall.

Description

The invention relates to techniques for transmitting and receiving data in mobile self-organizing wireless communication systems.

A known wireless communication method for controlling communication lines, operating time and state of a mobile device by transmitting control information in a frame through a wireless communication control device and a control channel for corresponding messages to a mobile device (RF patent No. 2391799) [1]. In this case, the mobile transceiver may be in an inactive state or in a communication mode, the time of which is determined by the content of messages in the frames of the control channel. The disadvantage of this method is the possibility of conflict at the input of the control unit when receiving applications for control of communication lines.

A known method of transmitting a point-to-multipoint service in a wireless communication system, which comprises the step of receiving a first message containing a first point-to-multipoint service group identifier associated with the first set of point-to-multipoint services for a given channel area (RF patent No. 2407189) [2]. The method also comprises the step of receiving a second message on a control channel containing a list of point-to-multipoint service identifiers associated with the first point-to-multipoint service group identifier. The method also includes a stage on which, in accordance with the control information received on the control channel, the lists of service identifiers are processed, if they contain at least one service. The technical result is the transfer of control information in accordance with the grouping of services on the network side of the mobile communication system in order to efficiently use radio resources. The disadvantage of this method is the cost of continuous processing of identifier lists with a small number of services.

A known system for channel allocation when releasing a connection using radio resources in dual-transmission mode, which uses a mobile device and a method adopted as a prototype, intended for use in wireless communication during the transition of a mobile device from dual mode, in which the connection is packet switched and a switched circuit connection is used together in a single mode in which packets are transmitted (RF patent No. 2404514) [3]. The technical result consists in providing a flexible distribution of packet transmission resources when a circuit switched connection is released in a dual transmission mode. To this end, when the circuit switched connection is released, packet resources are allocated by converting the time slots used for the channel circuit connection schedule to the time intervals used for the packet data schedule. At the same time, a new alert signal is included in the existing message transmitted to the mobile device to inform the mobile device that, after releasing the circuit switched connection, the specified conversion will occur. The disadvantage of this method is that the positive effect is manifested only when the size of the packet data graph, which ensures the presence of the packet queue in the mobile device. In the absence of a packet queue, the use of the method does not have a positive effect, since the time interval is rigidly assigned to the circuit switched connection and transmitted regardless of the size of the packet data graph. In addition, the method does not provide for the use of time intervals, the possibility of which is not excluded with a low schedule of packet data, which is also a disadvantage of the method.

The objective of the invention is to increase the efficiency of use of the radio resource of the communication system as a whole.

The problem is solved by using a method of transmitting a data stream in a wireless communication system in a mobile device, in which two switching methods are used separately or jointly in accordance with the value of the data stream, which makes it possible to rationally use the radio resource of the system as a whole. In case of single applications for communication, when the total schedule is minimal, the mobile device either performs a switching mode as part of a connection with the switching of dedicated channels, transmitting information from the previous mobile device to the next, or is in reception mode. With the growing number of communication applications and data flow, an increasing number of mobile devices that were in receive mode are being consistently included in the connection structures with switching of dedicated channels. At the moment when the last mobile device, which was in standby mode, is included in the structure of the connection with circuit switching, the next application for communication will result in the requirement for the organization of connection for switching another channel to the mobile device switching the dedicated channel. In this case, the mobile device enters packet switching mode, receiving packets, writing them to the buffer storage device and transmitting them according to the “first in, first out” rule

The method is implemented in a communication system consisting of unified mobile devices, each of which, when turned on, becomes a network node and can be in the following modes:

- in the reception mode, in which the packet preamble is decoded (addresses and command fields) in order to detect a call to the communication as the end user or

- a communication mode (relaying - receiving and transmitting packets or packet switching), in which the packet preamble is analyzed and, if there is no call to the communication as the end user, a new preamble is formed, a packet is transmitted or, if there is a packet queue, packet data switching is performed, at the end of which, a transition to the packet reception mode is performed.

From the second state, the mobile device can transition to the state of the end user by accepting its own address in the preamble of the packet and then issuing a message about it to mobile devices located in its coverage area.

To transmit data, the mobile device operates with packets of two sizes: short - in signaling mode, and long - in communication mode. The size of the short packet is affected by the length of the address part of the packet, determined by the quantitative composition of the system.

Since the method involves the separate or joint use of types of switching, taking into account the current value of the data stream, the description of the method and the application of connections with circuit switching and packet data switching are given in ascending order of the data stream from the minimum to the maximum and vice versa.

The mobile device initiating the creation of the communication channel generates a packet containing its own address, the address of the end user, the “Alarm” command, and transmits it n + 1 times with an interval corresponding to the duration of the short packet to ensure that all mobile devices located in it receive the packet coverage area, including relaying long packets, and then goes into receive mode. The number n is the quotient of dividing the duration of a long packet by the duration of a short one. The presence of the “Alarm” command in the transmitted packet for the mobile devices that received this signal means that the transmitter is a priority.

Mobile devices located in the coverage area of the priority mobile device, by the "Alarm" command, start priority counters, in which their address is recorded, and prepare information for transmission. The clock frequency of the priority counter is inversely proportional to the duration of the short burst. The mobile device, the address score at which will end earlier than the others, transmits a short packet consisting of the incoming address (address of the priority mobile device), its address and the signal-to-noise ratio at the receiver input. The next packet of the same structure will be transmitted by a mobile device whose address is greater than the previous one, but less than the addresses of the others in the coverage area. Thus, the transmission of short packets is carried out by devices sequentially in ascending order of their own addresses with the separation of packet transmission in time.

Mobile devices that are end-users, regardless of the result of deciphering the address of the end-user, form and transmit a short packet containing their own address, incoming address (address of the priority mobile device) and the Busy command. Having received a packet with the address of the final mobile device, the priority mobile device blocks this and other addresses of the end users located in its coverage area. If among these addresses there is the address of the called mobile device, information “Busy” is displayed on the display of the priority mobile device. Mobile devices that are in communication mode and are not end-users place a sign of operation in communication mode in the preamble of the package. The priority mobile device remembers the addresses of these devices. If among these addresses there is the address of the called subscriber, the called mobile device transmits in a short packet a receipt about the end of the Alarm mode, remaining in communication mode. Upon receipt of the receipt, the priority mobile device implements a direct communication channel, transmitting long packets. At the end of the communication session, the priority mobile device transmits a short packet containing the “End” command, after which it switches to receive mode.

If all or most of the mobile devices are in reception mode in the coverage area of the priority mobile device, the priority mobile device limits the analysis of received packets to the number k. The value of k is selected taking into account the magnitude of the allowable delay in the communication line. From this number of devices, the following mobile device is determined to the maximum signal-to-noise ratio, to which a packet is transmitted containing the address of this device, the priority device address, the address of the final mobile device, and the Alarm command. After that, the priority mobile device goes into receive mode. Having received the “Alarm” command, the next mobile device becomes the first node of the dedicated communication channel and, at the same time, priority over mobile devices located in its coverage area. As a priority mobile device, it performs the operations described above, forming the next node of the dedicated communication channel.

The sequential execution of such operations is completed in the subscriber’s mobile device by receiving his address and the “Alarm” command, having received which, the device transmits the next packet in the reverse direction through the nodes of the dedicated channel containing its address, the address of the previous (priority) mobile device and the receipt of completion Alarm mode. Upon receipt of the receipt, the mobile device that initiated the communication session, organizes the communication session by sending long packets. Long packets follow with an interval between them equal to the duration of the short packet. At the end of the communication session, the mobile device transmits a short packet containing its address, the address of the next mobile device in the dedicated channel, and the “End” command. By this command, all mobile devices of the dedicated channel, with the exception of those operating in dual mode, sequentially switch to receive mode.

If all mobile devices are in communication mode in the coverage area of the priority mobile device, the priority device selects one of them as described above. After that, the priority mobile device transmits a short packet n + 1 times, containing, inter alia, the address of the selected device and the “Alarm” command. Having received a new end-user address, this device enters packet switching mode.

An increase in the number of applications for communication and data flow leads to the fact that all mobile devices that were in standby mode turn out to be connected to circuit-switched connections. At the next application for communication, there is a need for connections with circuit switching through mobile devices operating as part of a dedicated channel when packets with different addresses come to their address. Having received packets with different addresses, the mobile device puts them in the queue and switches to packet switching mode, remaining in the structure of the dedicated channel that has switched to double transmission mode, the nodes of which can be mobile devices operating both in packet switching mode and in connection mode with switching a dedicated channel. Further growth of data flow will lead to the transition of the maximum number of mobile devices to packet switching mode. If all mobile devices of the communication system operate in the packet switching mode, the single data transmission mode is implemented.

When the data flow decreases, the mobile device initiates the transition to creating a circuit-switched connection when the device receives packets with a single destination address for some time, or when there are no packets, into the receive mode, which significantly increases the efficiency of using the energy and radio resources of the communication system.

Concrete implementation example

Numerical data for a wireless mobile communication system for 1000 subscribers: transmission rate 1028 kbit / s, duration of short packets - 50 bits (three addresses 30 bits, command field 10 bits, relay processing plus 10 bit reserve), long - 250 bits / s (information 200 bits, preamble 50 bits).

The amount of delay (rounded) during transmission between two nodes is 1 interval (min.), Between the 1st and 1000th nodes there are 999 intervals (max.):

- short burst: minimum 1 × 50 μs = 50 μs, maximum 999 × 50 = 50 milliseconds;

- long burst: minimum 1 × 250 = 250 μs, maximum 999 × 250 = 250 milliseconds.

The number n = 250/50 = 5, the number k = 3-5 affects only the delay value of a short packet.

The main difference of the proposed method is the lack of a single access point and a significant increase in the reliability of the system as a whole - the most important characteristic of the use of radio resource [4].

Differences in accessing the line

1. The use of two types of switching separately and together taking into account the intensity of the data stream

2. Reducing collision time when using two switching methods together.

3. A significant reduction (up to elimination) of collisions in the mode of connections with circuit switching.

Information sources

1. RF patent No. 2391799.

2. RF patent No. 2407189.

3. RF patent No. 2404514 - prototype.

4. V.M. Vishnevsky Theoretical foundations of the design of computer networks. M .: Technosphere, 2003, Ch. 9.

Claims (1)

A method of transmitting a data stream in a wireless communication system, including packet switching and a circuit switched connection, in which mobile devices are switched from a dual transmission mode to a single mode, in which only packets are transmitted, characterized in that the two types of switching are used separately or jointly in in accordance with the value of the data stream, which makes it possible to rationally use the radio resource of the communication system, moreover, with single applications for communication and a small data stream, connections are made to the switching th channel and packet transmission between mobile devices in communication mode, while mobile devices that are not involved in connections and are in standby mode, are sequentially included in the circuit-switched connection structure with increasing data flow and when the last mobile device enters communication mode, the next application for communication will lead to the transition of some mobile devices to packet-switched mode, and with the growth of data flow, packet-switching mode applies to all mobile devices of the system ligature, and with a decrease in the data stream are returned to the data transmission mode connections with circuit-switched and a transition to standby mode mobile devices that do not participate in such compounds.