SU1739501A1 - Device for controlling data transmission over radio channel - Google Patents

Abstract

The invention relates to a data transmission technique and can be used in the construction of information and computer networks based on broadcast packet radio communications. The purpose of the invention is to avoid collisions in the radio channel of various subscribers by ensuring the order of their release to the transmission. The device for controlling data transmission over the radio channel contains a pulse counter 1, a trigger 2, an AND 3 element, an OR 4 element, an OR-NOT 5 element, and a pulse shaper 6. The essence of the invention consists in ensuring the non-conflict work of the subscribers and the absence of the requirement for the synchronism of the device operation in the network. 1 il.

Description

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The invention relates to a data transmission technique and can be used in the construction of information computer networks based on broadcast packet radio communications.

The aim of the invention is to eliminate collisions in the radio channel of various subscribers by ensuring the order of their release to the transmission.

The drawing shows a structural electrical circuit of the device for controlling data transmission over the radio channel.

The device contains a pulse counter 1, a trigger 2, elements AND 3, OR 4 and OR-NOT 5 and a pulse shaper, made in the form of a single vibrator 6.

In the initial state, trigger 2 was reset, and counter 1 recorded the code for the number of this device (subscriber) in the network. Each network device has its own individual number; therefore, in various devices, counters 1 are in different states.

After switching on the network starts the device, the counter 1 of which is set to the zero state. Consider the operation of a single device, for example, the Mth device.

After switching on the network, the device monitors the presence of an external carrier signal at the device input. With each occurrence of a single signal at the input of a carrier, which indicates transmission in the channel (generally by another subscriber), counter 1 on the leading edge of this signal decreases its state by one. When the counter 1 reaches the zero state — on the falling edge, the next signal at the input of the carrier device (on the leading edge of this signal, the counter 1 has passed into the zero state), and a single signal appears at the output of the OR-NOT 5 element. On the front of the front of a single signal generated at the output of the element OR NOT 5, the one-shot 6 forms at its output a single impulse that through the element OR 4 goes to the output of the device and allows the transmitter to be turned on for the time determined by the duration of this impulse. The carrier signal in the radio channel that appears after switching on the transmitter leads to the appearance of a single signal at the inputs of all devices of the network.

If it is necessary to start the transmission, the subscriber exposes a single signal to the device request input. This signal opens element 3. At the same time, after zeroing of counter 1, in the same way as described case, the one-shot 6 forms a single impulse at its output. This pulse enters through the IL-4 element 4 to the output of the device and, moreover, through the AND 3 element to the input of the trigger 2, and the latter passes into the unit state. Single output signal

trigger 2 arrives at the output of the device and permits the information to be transmitted to the subscriber; in addition, it arrives at the input of the element OR 4; therefore, after the end of the pulse generated by the one-shot 7, a single signal remains at the output of the device.

After transmitting the information, the subscriber removes a single signal for the millet from the input of the device and trigger 2 is zeroed. As a result, single signals disappear at the device outputs.

Next, the device again controls the appearance of an external carrier signal at the device input.

0 Thus, when the device is granted the right to transmit (determined by the zero state of counter 1), either a short pulse is transmitted in the absence of a request for transmission from the subscriber,

5 or the transfer of information, if such a request is received.

Since in the initial state in the network devices, the counters 1 are in different states (from 0 to N-1, where N is the number of devices in the network) and the change in the states of these counters occurs by the same carrier signals - when transmitting over the radio channel either a pulse or information, after each transmission in the network there will be a single device with the right to transmit (counter 1 in the zero state), which excludes collisions in the radio channel of various subscribers.

Claims (1)

Invention Formula 0 A device for controlling data transmission over the radio channel, containing a pulse counter, as well as a series-connected element AND, a trigger and an OR element, another input of which is connected by a pulse driver, the first input of the element AND is connected to the inverse of the trigger input and is an input of the signal request of the device, the output of the transmission enable signal and the output of the transmitter control switching signal of which are, respectively, the trigger output and the output of the IL AND element, so that avoiding collisions in the radio channel of various 5 subscribers by providing the order of their exit to the transmission, an OR-NOT element is entered, the counting input of the pulse counter is connected to the first OR-NOT element, to the other inputs of which the outputs of the pulse counter are connected, and the output the element OR-NOT through the pulse shaper is the input of the carrier signal, the pulse is connected to the second input of the element, the installation inputs of the pulse counter of the mentator AND, and the counting input of the counter is named after the Subscriber ID code.