RU2280949C2 - Signal transmitting and receiving system using radio channel - Google Patents

Abstract

FIELD: electrical and radio engineering.

SUBSTANCE: proposed system designed for transmitting remote indication signals, telemetering from first, second, third through N^th controlled stations over radio channel to common supervisor station has only one transmitter installed in controlled station and only one receiver, in supervisor station. Each controlled station incorporates random-number generator for shaping signal repetition periods. Mobile controlled and supervisor stations can be used.

EFFECT: ability to afford equal operating conditions for controlled stations.

1 cl, 1 dwg

Description

The invention relates to the field of electro-radio engineering and may find application in systems for transmitting tele-signaling (TS), telemetry (TI) signals from the 1st, 2nd, 3rd, ... Nth monitored points (CP) over the air to General Dispatch Station (DP).

A device is known for a three-phase low voltage power line, (patent No. 212285, 6 H 04 B 3/54, 1998).

The main disadvantage of the known technical solution is the loss of performance in the absence of galvanic communication over the wires of a three-phase line (0.38-10-35) kV between the gearbox and the DP.

Also known is a device for transmitting and receiving signals over a radio channel (patent No. 2186461, 7 H 04 B 3/54, 7/00, 2002, July 27, 2002, Bull. No. 21), which is taken as a PROTOTYPE.

The main disadvantage of the PROTOTYPE is the presence of a power line, with the help of which the formation of signal repetition periods for each gearbox is performed, which does not allow the transmission of signals from vehicles and vehicles from moving objects.

In the claimed system, this drawback is eliminated, while, as in the prototype, only transmitters are installed on the CP, on the DP only the receiver.

The drawing shows a block diagram of a "System for transmitting and receiving signals over the air", which implements the claimed technical solution, where:

1. KP1

2. Transmitter KP1

3. Block for generating periods of signal transmission (block for forming) KP1

4. Random number generator (RNG) KP1

5. Transmitting antenna KP1

6. KPN

7. Transmitter KPN

8. Block forming KPN

9. RNG KPN

10. Transmitting antenna KPN

11. DP

12. DP receiver

13. Receiving antenna DP

SYSTEM OPERATION

At each control unit, the numbers 1, 2, 3, 4, 5, 6, 7, 8, 9 come from the RNG to the inputs of the forming units, and each random number has its own signal transmission period (period)

the number 1 corresponds to the period T ₁

number 2 - - - - T ₂

the number 9 corresponds to the period T ₉

These periods form in the blocks of the formation of each KP.

The information inputs of the transmitters KP1, KP2, KP3, ... KPN receive information from the TS, TI in the form of a sequence of video pulses, where they are converted into radio signals that are transmitted using transmitting antennas to the DP.

In the receiver DP, which receives the radio signals through the receiving antenna, they are processed in one of the known ways, as a result of which the sequence of video pulses for determining the information of the vehicle and the transceiver is again obtained at the information output of the receiver.

IMPLEMENTATION OF THE INVENTED TECHNICAL SOLUTION

DANO:

1. N = 500 - the number of KP

2. τ _u = 0.1 · 10 ^-3 sec - the duration of the transmission of one radio pulse. The value of τ _{u is} chosen from the following considerations: The State Committee for Radio Frequencies of the USSR, by a decision of November 15, 1978, No. 665, allowed to use frequencies for the development and operation of radio telesignals in the range (162.15-168.075) MHz. Based on the allowed emission band, which was allocated and equal to ΔF = 20 kHz, the duration of the radio pulse is equal to:

3. The amount of information in the packet of radio pulses is 50 Bit, then, taking into account (1), the duration of the packet of radio pulses from each CP will be equal to:

4. T _H = 3600 · 24 = 86400 sec = 1 day - the time of monitoring the operation of the system that implements the claimed technical solution.

5. m = 1 is the number of coincidence of signals at the input of the receiver of the common DP from any two CPs during the observation time, i.e. for 1 day.

DETERMINE PROBABLE SYSTEM CHARACTERISTICS:

1. T _cf - the average duration of the periods of transmission of signals at each controlled point.

2. The duration of the periods of transmission of signals at each controlled point

T ₁ , T ₂ , T ₃ , ... T ₉

- количество произведенных опытов за время наблюдения за работой системы Т_Н, т.е. за 1 сутки.3.

- the number of experiments performed during the observation of the operation of the system T _N , i.e. for 1 day.

- вероятность наступления события А за время наблюдения за работой системы Т_н, т.е. за 1 сутки.four.

- the probability of occurrence of event A during the observation of the operation of the system T _n , i.e. for 1 day.

Where: A - an event characterizing the coincidence on DP signals from any two CPs.

It should be noted that the signals from all CPs will be randomly distributed on the time axis and their coincidence in the time interval Δt = τ _p = 5 · 10 ^-3 sec according to (2) will correspond to the Poisson probability law, because the following conditions are met: [1]

1. The flow of events (signals coming from the CP) - ORDINARY;

2. The flow of events is STATIONARY;

3. The flow of events - DOES NOT HAVE CONSEQUENCES;

The ORDINARY condition means that the signals from each dispersed KP come to the common DP receiver individually, and not in pairs, triples, etc.

The STATIONARY condition is satisfied by the flow of events, the probabilistic characteristics of which are independent of time. A stationary flow is characterized by a constant flux density λ _cf , i.e. average number of events (signals) arriving at the DP receiver per unit time

where: N - the number of KP working on one DP

T _cf - the average duration of the periods of transmission of signals from each KP to DP, which is a constant value. From (3) it follows that λ _cp = const and means the constancy of events (signals) per unit time.

The NO CONSEQUENCE condition means that the events (signals) enter the system (to the common receiver DP) independently of each other.

Poisson's law has the form:

where: z is the number of events (signals) that coincide with each other, in a selected time interval Δt. In our example, z = 2, Δt = τ _p .

We are interested in the coincidence of signals from two different CPs in the time interval Δt = τ _p , because in this case, the signals at the input of the receiver DP coincide and will not be received. They will be received in the next transmission cycle. We assume, from the condition of problem p. 5, that with probability P (A), such a situation occurs once a day, i.e. m = 1. l is the base of the natural logarithm.

Thus, taking into account the above, expression (4) will take the form:

тогда (5) примет вид:In the future, we show that the quantity α≪1, and therefore, we can take the quantity

then (5) takes the form:

where: α is the Poisson parameter, is the mathematical expectation of the number of signals falling in the time interval Δt = τ _p = 5 · 10 ^-3 sec

where: λ _cf (t) is the average flux density.

т.е. соответствует выражению (3)In our case:

those. corresponds to the expression (3)

Therefore, solution (7) has the form:

substituting (8) in (6), we obtain:

On the other hand, according to the claims we have [2]:

We equate the right parts of expressions (9) and (10)

We solve the expression (11) with respect to T _cf

Under the conditions set for the implementation of the method, we took the value m = 1, i.e. we admit one coincidence of two signals from different controllers during the observation of the operation of the T _n system for 1 day. With this in mind, expression (12) will take the form:

Define the value of T _cf taking into account the source data:

N = 500, τ _p = 5 · 10 ^-3 s, T _N = 86400 s

Define according to the claims the period T ₁

Define according to the claims the values of the periods T ₂ -T ₉ :

T ₂ = 2T ₁ = 2 × 13 = 26 sec

T ₃ = 3T _l = 3 × 13 = 39 sec

T ₄ = 4T ₁ = 4 × 13 = 52 sec

T _cf = T ₅ = 5T ₁ = 5 × 13 = 65 sec

T ₆ = ₆ T ₁ = 6 × 13 = 78 sec

T ₇ = 7T ₁ = 7 × 13 = 91 sec

T ₈ = 8T ₁ = 8 × 13 = 104 sec

T ₉ = 9T ₁ = 9 × 13 = 117 sec

Define n - the number of experiments during the observation of T _n the operation of the system, i.e. for 1 day

We determine the probability of P (A) according to the claims taking into account (15) [2]

Define the value of α - the Poisson parameter from (8)

We calculate l ^α = 1.04. This means that the adoption of l ^α ≈1 in expression (5) is fair.

Thus, we have proved that the goal set by the invention has been achieved, while a new technical result is obtained when transmitting signals of a TS, TI from a distributed KP to a common DP:

1) The power line has been eliminated, with the help of which signal repetition periods were formed in PROTOTYPE, which allows the use of a mobile DP and mobile gearboxes in the proposed technical solution.

2) In the PROTOTYPE with a large number of KP there will be a large spread in the values of T ₁ and T _N , i.e. during one period of operation of gearbox _N , gearbox ₁ will be transmitted several times, which creates UNEQUAL working conditions between gearboxes. In the proposed technical solution, ALL KP are in the same conditions and ALL have the same average follow-up period T _cf. In this regard, for each control unit in PROTOTYPE there should be an individual unit for the formation of signal repetition periods. In the proposed technical solution, all CPs have the same blocks for generating periods of signals and the same random number generators, which is very important for production.

Literature:

1. E.S. Wentzel. Probability theory. M .: "Science", 1964

2. E.S. Wentzel, L.A. Ovcharov. Probability theory. Science, 1973

Claims (1)

System Tsagareishvili S.A. transmitting and receiving signals over a radio channel in which there are N = 1, 2, 3, ..., N monitored points, a common control room, while at the controlled point they have a block for generating periods of signal transmission, the output of which is connected to the first input of the transmitter, the output of which is connected to the input of the transmitting antenna, the second input of the transmitter is informational, at the control room a receiver, the input of which is connected to the output of the receiving antenna, characterized in that a random number generator is introduced at each controlled point, the output It is connected to the input of the signal-transmission periods.