RU53521U1 - NOISE SIGNAL TRANSMITTER - Google Patents

Abstract

A ShPS transmitter is proposed, characterized by the presence of a single-band ShSS shaper by the phase compensation method, which allows to double the ShPS base in the allocated frequency band and thereby increase the noise immunity and noise immunity of the transmission, transmission secrecy, and the accuracy of determining the object's motion parameters.

Description

The invention relates to the field of radio transmitting devices.

Known transmitters of noise-like signals (SHPS), described in various sources, for example in:

1. Varakin L.E. Communication systems with ShPS. - M .: Radio and communications, 1985

2. ShPS in information transmission systems / Ed. V.B.Pestryakova - M .: Sov. Radio, 1973

3. RF patent №2259632. The method of dividing the frequency band of the transmitted signal and a device for its implementation / A.A. Volkov. Priority from 03.24.04.

By technical nature, the device closest to the utility model is described in the first source, which for this reason is taken as its prototype.

The SHPS prototype transmitter consists of a series-connected information source, a signal multiplier, a balanced modulator, an amplifier, as well as a ShPS carrier generator, connected with its output to the second input of the multiplier, and a carrier frequency oscillation generator connected to the second input of the balanced modulator, synchronizer, through which is connected to the source of information of the generator ShPS.

The main disadvantage of the prototype is the inefficient use of the allocated frequency band, which does not allow to maximize the base of the NPS without reducing the speed of information transfer and thereby maximize the main advantages of the NPS:

1. noise immunity and noise immunity of the transmitted information;

2. stealth transmission;

3. the accuracy of measuring the motion parameters of the object;

4. minimization of the influence of the electromagnetic field on the human body, etc.

The technical result of the utility model is a 2-fold increase in the NPS base in a given frequency band without reducing the speed of digital information transmission and a corresponding increase in the above indicators.

The essence of the utility model consists in the use of a single-band ShPS in the developed shaper instead of a two-band (balanced) modulator in the transmitter. Now, in a given band F, there are not two, but one side frequency band F ₀ ШПС, the width of which can be increased by 2 times and, therefore, increased by 2 times the base of ШПС B = FT, where Т is the duration of the elementary sending of digital (modulating) signal.

Such a shaper was implemented by adding a second balanced modulator, a 90 ° phase shifter of the carrier frequency oscillation, two phase inverters, two splitters of the NPS phase 2 times, and an adder.

A significant difference between the utility model is the totality of the introduced elements and their relationships, because only they make it possible to ensure a 2-fold increase in the base of ShPS and the above indicators.

The proposed utility model is illustrated by drawings.

Figure 1 presents the structural diagram of the transmitter, and figure 2 is a timing diagram explaining its operation.

The transmitter consists of an information source (digital) 1, a synchronizer 2, a signal multiplier 3, a generator of a ShPS-carrier (subcarrier) 4, a filter of information ShSS 5, phase inverters 6, 14; dividers 7, 8 of the phase of the ШПС by 2, balanced modulators 9, 12, oscillator of half-carrier frequency 10, phase shifter by 90 ° carrier 11, adder 13, frequency doubler 15, amplifier 16.

Entered elements are outlined with a dashed line. Blocks 5-13 are a shaper of a single-band ShPS by phase compensation method.

The operation of the circuit is as follows.

At the input of block 1, an analog (speech) signal is supplied, which is converted into an alternating digital signal (DS) with an elementary transmission of duration T, as shown in FIG. 2. This CA is fed to the information input of the multiplier 3, the second input of which is supplied with a ShPS carrier (subcarrier) also of a rectangular shape from block 4, as shown in Fig. 2. The beginning of the NPS codogram exactly coincides with the beginning of the elementary sending of a digital signal, which provides synchronizer 2. The duration of the elementary sending of the NPS is τ ₀ ≪Т. Since the digital signal is alternating, at the output of the multiplier 3 there will be a phase-shifted (FM _n ) 180 ° oscillation u _p1 (t) (Fig.2) subcarrier digital signal. This FM _n oscillation is an informational BSS u _n1 = (t) = Ucos [ω ₁ t + γ (t) Δφ], where γ (t) = ± 1 is the law of the sign of the digital signal, and Δφ = 90 °.

As a result of the multiplication, the digital signal has an elementary packet also equal to τ ₀ , which is why its band increases by T / τ ₀ = TF = B times, where B is the base of the BPS. It is seen that В≫1.

In order not to double this band and, at the same time, to increase the base of SHPS by 2 times, it is proposed to transfer the information SHPS to the operating frequency of the transmitter by means of single-band amplitude modulation (AMP AM) instead of the two-band (balanced) used in the prototype.

The formation of AMP AM must be carried out by phase compensation method. From the output of the multiplier 3 SHPS passes filter 5, where it transforms its rectangular shape into a quasi-harmonic

and arrives at the information input of the divider 7. This method of phase shift by 90 ° ШПС is the only possible one due to the presence of synchronizer 2. From the output of block 7 it goes to the information input of the balanced modulator 9, and from the output of block 8 to the information input of the balanced modulator 12. С oscillator 10, the half-carrier frequency oscillation u ₁₀ (t) = U ₁₀ cos0.5ω ₀ t goes directly to the second input of the balanced modulator 9 and to the second input of the balanced modulator 12 through a 90 ° phase shifter 11. At the output of blocks 9, 12 we have voltages :

u ₉ (t) = u ₇ (t) u ₁₀ (t) = U ₇ cos0.5 [ω ₁ t + γ ₁ (t) Δφ] U ₁₀ cos0.5ω ₀ t =

0.5U ₇ U ₁₀ {cos0.5 [(ω ₀ + ω ₁ ) t + γ (t) Δφ] + cos0.5 [(ω ₀ -ω ₁ ) t-γ (t) Δφ]}

u ₁₂ (t) = u ₈ (t) u ₁₁ (t) = U ₈ cos0.5 [ωt + γ (t) Δφ + 180 °] U ₁₁ cos0.5 (ω ₀ + 90 °) =

0.5U ₈ U ₁₁ {-cos0.5 [(ω ₀ + ω ₁ ) t + γ (t) Δφ] + cos0.5 [(ω ₀ -ω ₁ ) t-γ (t) Δ (φ]}

Moreover, U ₇ = U ₈ , U ₁₀ = U ₁₁ .

The oscillation u ₉ (t) goes to one input of the adder 13 directly, and u ₁₂ (t) - to the second input of the adder directly or through a phase inverter 14. When directly connected u ₉ (t) and u ₁₂ (t) to block 13 we have half lower sideband (NBP):

u ₁₃ (t) = u ₉ (t) + u ₁₂ (t) = U ₇ U ₁₀ cos0.5 [(ω ₀ -ω ₁ ) t-γ (t) Δφ]

And when you connect u ₁₂ (t) through the phase inverter 14 value

u ₁₃ (t) = u ₉ (t) -u ₁₂ (t) = U ₇ U ₁₀ cos0.5 [(ω ₀ + ω ₁ ) t + γ (t) Δφ] is the half upper lateral frequency band (PFS) . In both cases (NBP and PWB), the frequency band of a single-band signal is equal to half the frequency band of the informational BSS on the subcarrier, which is what the goal is achieved.

From the output of the adder 13, the signal doubles in frequency in block 15, after which it is amplified in block 16 and emitted by antenna A. When the frequency is doubled, Δφ changes from 45 ° to 90 °, thereby ensuring the highest noise immunity of the communication.

Note that since the modulating signal is an alternating digital one, then single-band modulation is not amplitude, but phase - OBP FM _n 180 °. In a given frequency band of the transmitter, using OBP FM _n instead of DBP FM _n , you can increase the base of BPS TF = 2 times and thereby increase the corresponding indicators. This determines the technical and economic effect of the utility model.

Claims (1)

Noise-like signal transmitter, consisting of a series-connected information source, signal multiplier, balanced modulator, amplifier, and a noise-like carrier signal generator connected to the second input of the multiplier and connected to the second input of the information source through a synchronizer, a carrier frequency generator connected to the second input balanced modulator, characterized in that it additionally includes a filter, two phase inverters, two signal phase divisors into two, the second balanced th modulator, 90 ° phase shifter, adder, frequency doubler, moreover, the multiplier is connected to the amplifier through a series-connected filter, the first signal phase divider by two, the first balanced modulator, adder, frequency doubler, while the filter output is connected to the second input of the adder through the first phase inverter, the second divider of the signal phase into two, the second balanced modulator, the second phase inverter, and the second input of the second balanced modulator connected to the output of the half oscillator in series esuschey frequency through a phase shifter 90 °.