JPH0553380B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is a synchronization device used in radar and communication systems, which emit radio waves to a target, receives reflected radio waves, and calculates the distance to the target. radar that requires high-speed synchronization of two-phase modulation for the purpose of measurement;
The present invention also relates to communication devices used in communication systems that require high-speed synchronization with high secrecy.

(Summary of the Invention) The present invention relates to a radar that transmits a pseudorandom signal to a target by 0 and π two-phase quadrature modulation, balanced quadrature modulation, or four-phase phase modulation,
In frequency spread communication using pseudo-random signals, it is possible to track the target signal by synchronizing the signals reflected from the target at high speed, and reduce the ambiguity associated with distance measurement. , π, when a signal created by two-phase quadrature modulation or balanced quadrature modulation is transmitted from the transmitter to the receiving side, in order to demodulate the modulated signal by reducing the communication failure time by high-speed synchronization of the received signal.
The communication device was improved to enable high-speed synchronization.

(Prior Art) The conventional example shown in FIG. 3 will be explained. Second transmission source output 117 which is the output signal of second transmission source 116
is the second modulation signal 1 which is the output of the second modulation/demodulation signal generator 170 in the seventh phase modulator 130
71 and becomes the seventh phase modulator output 131, which is input to the second transmitter 122 and amplified to become the second transmitter output 123, which is then transmitted from the second transmitting antenna 110 to the second transmission signal 111. is sent to the target.

Second received signal 113 which is a reflected wave from the target
is received by the second receiving antenna 114 and becomes the second receiving antenna output 115, and the fourth power divider 14
2, and the power of the received signal is distributed to the 4th
They become a power divider first output 143 and a fourth power divider second output 145. 4th power divider 1st output 1
43 is multiplied by the fifth demodulation signal 135, which is the output of the eighth phase modulator 134, as the demodulation signal in the fifth demodulator 154, and becomes the fifth demodulator output 155, which is then sent to the fifth intermediate frequency amplifier 162. Input and amplified fifth intermediate frequency amplifier output 163
Thus, one output of the fifth intermediate frequency amplifier output 163 is input to the third synchronous detector 124.

The fourth output which is the other output of the fourth power divider 142
The power divider second output 145 is connected to the sixth demodulator 156
, which is the output of the ninth phase modulator 136 at
A multiplication operation is performed using the demodulation signal 137 as the demodulation signal, resulting in the sixth demodulator output 157, which is input to the sixth intermediate frequency amplifier 164 and amplified to become the sixth intermediate frequency amplifier output 165, which is the sixth intermediate frequency amplifier output 165. is input to the third synchronous detector 124 and is synchronously detected using the fifth intermediate frequency amplifier output 163 as a reference signal.
This becomes the synchronous detector output 125 and is input to the second modulation/demodulation signal generator 170. The first signal 17 for second demodulation is the output of the second modulation/demodulation signal generator 170
3 is the second local oscillator output 18 which is the output of the second local oscillator 182 in the eighth phase modulator 134.
3, and a fifth demodulation signal 135 is obtained as the output of the eighth phase modulator 134. The second output, which is the other output of the second modulation/demodulation signal generator 170
The second signal 175 for demodulation is the second local oscillator output 1
83 modulation signal, and the ninth phase modulator 136
A phase-modulated sixth demodulation signal 137 is created.

The other output of the fifth intermediate frequency amplifier output 163 is input to an amplitude detector 190 and subjected to amplitude detection to become an amplitude detector output 191, which is used for target detection.

(Problems to be Solved by the Invention) In the conventional example shown in FIG.
and the second received signal 113 are _respectively set as X ₁₁₁ = _a (t ₎ sinωt...(1) However, a(t) is an amplitude modulation term due to phase modulation, and is represented by a pseudorandom signal (for example, a pseudorandom code sequence) with a constant period. T ₀ is the propagation time from transmission to reception, and ω is the angular frequency of the carrier wave.

The fifth demodulation signal 135 is set as X ₁₃₅ =a(t+τ) cosω _r t (3). However, ω _r is the angular frequency of the demodulation signal, τ
is the out-of-synchronization. The sixth demodulation signal 137 is set as X ₁₃₇ =A(t+τ) cosω _r t (4). However, A(t) is a pseudorandom signal (for example, a pseudorandom code sequence) with a constant period orthogonal to a(t).

The fifth intermediate frequency amplifier output 163 is obtained by integrating the second received signal 113 and the fifth demodulation signal 135 after the multiplication operation, so that X ₁₆₃ =ρ _aa (τ) sinω _i t (5). However, ω _i =ω−ω _r ……(6) ρ _aa (τ) = ∫a(t) a(t+τ) dt……(7), and ρ _aa (τ) is the autocorrelation with respect to a(t). It is a function.

The sixth intermediate frequency amplifier output 165 is obtained by integrating the second received signal 113 and the fifth demodulation signal 135 after the multiplication operation, so that X ₁₆₅ =η _aA (τ) sinω _i t (8). However, η _aA (τ)=∫a(t)A(t+τ)dt...(9), and since a(t) and A(t) are mutually orthogonal signals, ∫a(t)A( t+τ)dt=0...(10). However, η _aA (τ) is an autoorthogonal correlation function between a(t) and A(t).

Since the third synchronous detector output 125 is the average after the multiplication operation of the fifth intermediate frequency amplifier output 163 and the sixth intermediate frequency amplifier output 165, X ₁₂₅ = E[η _aA (τ) ρ _aa (τ)]... …(11) becomes. However, E[ ] represents the average. This equation (11) is an error signal called S-characteristic required for synchronization.

Assuming that the pulse width of 1 bit is K (seconds) and the length of the code sequence that is the modulation signal is L (bits), there is no ambiguity in distance measurement due to the loopback of the target signal that occurs every period of the code sequence. The distance R (meters) is R=C×K×L (12). However, C (meter/second) is a constant. Similarly, the maximum synchronization time T (seconds) required for synchronization of the target signal is T=k×L (13). However, k is the time required to determine the presence or absence of a reflected wave signal from the target for each bit, and is a constant. In this way, when the target is far away from the starting distance of the search, there is a drawback that it takes time to synchronize. Therefore, the biggest challenge in spread spectrum communication is high-speed synchronization pull-in.

(Means for Solving the Problems) In order to solve these problems, the present invention uses two types of pseudo-random signals with low mutual correlation to achieve two-phase quadrature modulation of 0 and π, balanced quadrature modulation, or balanced quadrature modulation. In order to transmit a radio wave type signal created by four-phase phase modulation and demodulate this transmitted signal, pseudo-random signals that are orthogonal to each of the two types of pseudo-random signals are used, and the necessary processing is performed. A synchronization device that obtains an error signal by using the same method and returns the error signal to a demodulation signal generation section to shorten the synchronization pull-in time and effectively lengthen the period of the pseudo-random signal. A radar and communication receiver equipped with the synchronization device is configured.

First, regarding the basic principle of the present invention, the first
This will be explained using the embodiment shown in FIG.

The transmitted signal ₁₁ and _{the received} signal 13 are respectively
T ₀ )]+b(t+T ₀ ) cos[ω(t+T ₀ )+ψ(t+
T ₀ )] ...(14) X ₁₃ =a(t)sin[ωt+φ(t)]+b(t)cos
[ωt+ψ(t)] ...(15) However, b(t) is an amplitude modulation term due to phase modulation, and is expressed by a pseudo-random signal (for example, a pseudo-random code sequence) with a constant period and low cross-correlation with a(t). The first demodulation signal 35 is set as X ₃₅ =a(t+τ)cos(ω _r t+α) (16). The second demodulation signal 37 is set as X ₃₇ =b(t+τ) sin(ω _r t+α) (17). However, α is an arbitrary phase of the demodulation signal. The carrier waves of the first demodulation signal 35 and the second demodulation signal 37 are orthogonal to each other. Third
The demodulation signal 39 is set as X ₃₉ =A(t+τ) sin(ω _r t+α) (18). The fourth demodulation signal 41 is set as X ₄₁ =B(t+τ)cos(ω _r t+α) (19). However, B(t) is a pseudorandom signal (for example, a pseudorandom code sequence) with a constant period orthogonal to b(t). Note that the first demodulation signal 35,
a(t), b for creating the second demodulation signal 37, the third demodulation signal 39, and the fourth demodulation signal 41
(t), pseudorandom signal A(t) which is orthogonal to a(t), and pseudorandom signal B(t) which is orthogonal to b(t), are generated by the demodulation signal generator 70b.
can occur in That is, the first signal for demodulation 75 is a(t), and the second signal for demodulation 77 is
is b(t), and the third signal for demodulation 79 is A(t).
The fourth signal for demodulation 81 outputs B(t). Third
The carrier waves of the demodulation signal 39 and the fourth demodulation signal 41 are orthogonal to each other. Since the first intermediate frequency amplifier output 63 is created by integrating the received signal 13 and the first demodulation signal 35 after the multiplication operation in the first demodulator 54, X ₆₃ =ρ _aa (τ) sin(ω _i t ) + ρ _ba (τ) × cos
(ω _i
t) ...(20). However, (ω _i t) indicates that it is a function of ω _i t. The third intermediate frequency amplifier output 67 is sent to the third demodulator 58 which outputs the received signal 13 and the third demodulation signal 39.
X ₆₇ = ρ _ab (τ) sin (ω _i t) + ρ _bb (τ) × cos
(ω _i
t) ...(21) becomes. However, ρ _aa (τ) = ∫a (t) a (t + τ) dt ... (22) ρ _ba (τ) = ∫b (t) a (t + τ) dt ... (23) ρ _ab (τ) = ∫ a(t)b(t+τ)dt...(24) ρ _bb (τ)=∫b(t)b(t+τ)dt...(25). For their respective physical meanings, ρ _aa (τ) is the autocorrelation function with respect to a(t), and ρ _bb (τ) is the autocorrelation function with respect to b(t).

Furthermore, since ρ _ba (τ) is a cross-correlation function between b(t) and a(t), it has the statistical property ρ _ba (τ)≈0 (26).

Since ρ _ab (τ) is a cross-correlation function with a(t) and b(t), it has the statistical property that ρ _ab (τ)≈0 (27).

Since the second intermediate frequency amplifier output 65 is created by integrating the received signal 13 and the second demodulation signal 37 after the multiplication operation in the second demodulator 56, X ₆₅ =η _aA (τ) sin(ω _i t )+η _bA (τ)×cos
(ω _i
t) ...(28) becomes. Since the fourth intermediate frequency amplifier output 69 is created by integrating the received signal 13 and the fourth demodulating signal 41 after the multiplication operation in the fourth demodulator 60, X ₆₉ =η _aB (τ) sin(ω _i t )+η _bB (τ)×cos
(ω _i
t) ...(29) becomes. However, η _aA (τ)=∫a(t)A(t+τ)dt...(30) η _bA (τ)=∫b(t)A(t+τ)dt...(31) η _aB (τ)= ∫a(t)B(t+τ)dt...(32) η _aB (τ)=∫b(t)B(t+τ)dt...(33) and a(t), A(t) and b (t) and B
(t) are made of mutually orthogonal pseudo-random signals, so ∫a(t)A(t)dt=0...(34) ∫b(t)B(t)dt=0...(35 ). Regarding their physical meanings, η _aA (τ) is a self-orthogonal correlation function between a(t) and A(t), and η _bB (τ) is a self-orthogonal correlation function between b(t) and B(t). η _aB (τ) is the cross-correlation function between a(t) and B(t), and η _bA (τ) is the cross-correlation function between b(t) and A(t). .

The first synchronous detector output 25 is the first of the first intermediate frequency amplifier output 63 and the second intermediate frequency amplifier output 65.
Since _it is created by _the average after the multiplication _operation in the synchronous detector 24, Since it is created by the average of the multiplications of the output 67 and the fourth intermediate frequency amplifier output 69, X ₂₇ =E[η _aB (τ) ρ _bb (τ)] ...(37). The first synchronous detector output 25 and the second synchronous detector output 27 have what is called the S-characteristic of the discriminator, and are error signals necessary for synchronization.

However, when τ is near zero, E[η _bA (τ)ρ _ba (τ)]≒0 ...(38) E[η _aB (τ)ρ _ab (τ)]≒0 ...(39) The code sequences for modulation and demodulation are selected as follows. For example, the code sequence a shown in equation (14)
(t) and b(t), as shown in Figure 6, there is a relationship of b(t)=a(t+T/2)...(39b) (where T is one period of the code sequence), etc. It is. In such a case, the relationships of equations (38) and (39) hold near τ≒0 (39c).
Even if the code series is the same, when codes with a sharp autocorrelation function ρ _aa (τ) and a cross-correlation function η _aA (τ) with small sidelobes, such as the M-sequence code, are shifted from each other by about 1/2 period, Formula (39c) as shown in Figure 6
Under the conditions, the relationships of equations (38) and (39) hold true.
Equations (38) and (39) hold true under the condition of Equation (39c) if the code sequences have a portion where the cross-correlation function is close to zero.

Note that the cross-correlation function η _aA (τ) in Fig. 6 is τ≒
0, has an S-shaped characteristic (η _aA (τ)ρ _aa (τ)
have similar S-shaped characteristics), so it is called the S-shaped characteristic. In Figure 6, A
(t), B(t), ρ _aa (τ), ρ _ab (τ), ρ _ba (τ
), η _aB
(τ) and η _bA (τ) are also shown.

Claims 7, 8, 9, and 1
The principles regarding the 0th term, the 11th term, and the 12th term will be explained.

In the second embodiment shown in FIGS. 4 and 5, it will be explained that synchronization can be maintained by the following simple method. Similarly, the received signal 13 is expressed as X ₁₃ =a(t)sin[ωt+φ(t)]+b(t)cos
[ωt+ψ(t)] ...(15). Since the first demodulation _signal 35a is generated by combining the power of the first demodulation signal ₃₅ and the _second demodulation signal ₃₇ , ) sin(ω _r t+α)
...(40), and the third demodulation signal 39a is the third demodulation signal 3
9 and the fourth demodulation signal 41, so X ₃₉ a=X ₃₉ +X ₄₁ = A(t+τ)cos(ω _r t+α) +B(t+τ) sin(ω _r t+α)
...(41). The first intermediate frequency amplifier output 63a is output from the first demodulator 5 of the received signal 13 and the first demodulation signal 35a.
X ₆₃ a=ρ _aa (τ) sin (ω _i t) + ρ _ba (τ) × cos (ω _i t) + ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t) ...(42).

The second intermediate frequency amplifier output 65a is the received signal 13
and the third demodulation signal _39a after _{the multiplication} operation in the second demodulator 56 _.

(ω _i t) + η _aB (τ) cos (ω _i t) + η _bB (τ) sin
(ω _i
t) ...(43) becomes. The first synchronous detector output 25a is the first intermediate frequency amplifier output 63a and the second intermediate frequency amplifier output 6.
X ₂₅ a=E{[η _aA (τ) + η _aB (τ)] [ρ _aa (τ
) +ρ _bb (τ)]} ...(44) As shown in Figure 6, the cross-correlation function η _aA (τ) has an S-shaped characteristic near τ≒0 (η _aA ( τ)ρ _aa (τ) also has a similar S-shaped characteristic), so this is called the S-shaped characteristic of the discriminator, and is an error signal necessary for synchronization. The S-shaped characteristic of the discriminator in Equation (44) shows that it is possible to make the S-shaped characteristic variable, such as by fixing one side and making the other variable to expand the pulling width. That is, the S-shaped characteristic can be varied by changing the weighting of power combination (to a value other than 1:1) using equations (40) and (41).

Claims 13, 14, and 15
The principles relating to Sections 1, 16, 17, and 18 will be explained.

Similarly, in the second embodiment shown in FIGS. 4 and 5, the received signal 13 is expressed as X ₁₃ =a(t) sin[ωt+φ(t)]+b(t) cos
[ωt+ψ(t)] ...(15). Since the first demodulation signal 35b is generated by power combination of the first demodulation signal 35 and the second demodulation signal 37, X ₃₅ b=X ₃₅ +X ₃₇ =a(t+τ) sin(ω _r t+α) +b(t+τ ) sin(ω _r t+α)
...(45). Since the third demodulation signal 39b is generated by power combination of the third demodulation signal 39 and the fourth demodulation signal 41, X ₃₉ b=X ₃₉ +X ₄₁ =A(t+τ) sin(ω _r t+α) +B(t+τ ) sin(ω _r t+α)
...(46). The first intermediate frequency amplifier output 63b is sent to the second demodulator 5 of the received signal 13 and the first demodulation signal 35b.
X ₆₃ b=ρ _aa (τ) cos (ω _i t) + ρ _ba (τ) × sin (ω _i t) + ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t) ...(47). The second intermediate frequency amplifier output 65b is output from the second demodulator 5 of the received signal 13 and the third demodulation signal 39b.
X ₆₅ b=η _aA (τ) cos (ω _i t) + η _ba (τ) × sin (ω _i t) + η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t) ...(48). The first synchronous detector output 25b is the first intermediate frequency amplifier output 63b and the second intermediate frequency amplifier output 6.
5b in the first synchronous detector 24, so X ₂₅ b=E[η _aA (τ)+η _aa (τ)] +E[η _bB (τ)+η _bb (τ)]... ...(49) This is an S-shaped characteristic and is an error signal necessary for synchronization. Therefore, even with this method, synchronization with the received signal 13 can be maintained. The S-shaped characteristic of the discriminator in Equation (49) shows that it is possible to make the S-shaped characteristic variable, such as by fixing one side and making the other variable to expand the pulling width.

(Function) From the above explanation, it has been explained that it is possible to configure a servo loop for synchronizing with the received signal 13, so the actually necessary synchronization time will be explained.

If the transmitted signal 11 is a continuous wave, the distance R (meters) that can be measured without ambiguity is M
If we assume that the bit length K (seconds) of and N is equal, we get R=C×K×LCM(N,M)...(50). Here, M is the code sequence length (number of bits) of the modulation signal a(t), N is the code sequence length (number of bits) of b(t), and LCM (N, M) is the integer N and M is the least common multiple of

The maximum synchronization time T (seconds) required for synchronization is T=k×N (51). However, N>M...(52). In the case of pulse modulation radar, R = C × K × LCM (N, M, P) ... (53) T = k × N ... (54). However, P is the pulse repetition time converted into bits.

Comparing equation (12) with equation (50) or equation (53), the code sequence of the modulation signal according to the present invention is
This shows that the ambiguity of the same distance is shorter, which means that the pull-in time required for synchronization is shorter.

As an example, let L=2 ²ⁿ −1 (55) in equation (13), and from equal ambiguity L=M×N ...(56) N=2 ⁿ +1 (57) M=2 ⁿ −1 (58) This results in the same ambiguity as when constructed using equations (57) and (58), and the synchronization pull-in time is (2 ⁿ −1).
It can be seen that there is a significant improvement effect.

Next, claims 4 to 6 and 10
A case will be described in which the periods of the code sequences related to the terms 1 to 12 and 16 to 18 are equal: aM=IN (59). Here, a is the bit length of the code sequence a(t), and b is the bit length of the code sequence b(t).
is the bit length of

Although this case has no effect on distance ambiguity expansion, separate synchronization pull-in circuits for the a(t) and b(t) channels are no longer required, and the maximum synchronization pull-in time T (seconds) required for synchronization is eliminated. ) becomes T=k×M ……(60). However, N>M...(52). As shown in equation (60), the maximum synchronization pull-in time T (seconds) required for synchronization is small when the number of bits M is small.
Therefore, it can be expected to be effective in shortening the synchronization pull-in time. Also, code sequences a(t), b
By making the periods of both code sequences variable while maintaining the period of (t) equal, the S-shaped characteristic of the error signal can be made variable, and synchronization in radar and communication devices can be facilitated.

(Example) Examples of the present invention will be described below with reference to the drawings.

First, a first embodiment shown in FIGS. 1 and 2 will be described. A first transmission source output 17 and a second transmission source output 19, which are outputs of the transmission source 16, are input to a first phase modulator 30 and a second phase modulator 32, respectively. In the first phase modulator 30, the transmission source first output 1
Reference numeral 7 denotes a first phase modulator output 3 which is phase-modulated using a first modulating signal 71, which is an output of a modulating signal generating section 70a of a modulating/demodulating signal generator 70, as a modulating signal.
Becomes 1. In the second phase modulator 32, the second phase modulator 32
The output 19 is phase-modulated using the second modulation signal 73, which is the output of the modulation signal generation section 70a of the modulation/demodulation signal generator 70, as a modulation signal, and becomes the second phase modulator output 33. The first phase modulator output 13 and the second phase modulator output 33 are respectively connected to the power combiner 20
The carrier waves are power-combined so as to be orthogonal to each other, resulting in a power combiner output 21, which is input to a transmitter 22, where it is amplified and becomes a transmitter output 23, and the transmission signal 11 is transmitted from the transmitting antenna 10 toward the target. .

The received signal 13, which is a reflected wave from the target, is received by the receiving antenna 14, becomes the receiving antenna output 15, and is input to the first power divider 42, and is transmitted to the first power divider first output 43 and the first power divider. A second output 45 is obtained. The first power divider first output 43 is the first
In the demodulator 54, the first demodulation signal 35 is demodulated as a demodulation signal to become the first demodulator output 55, which is input to the first intermediate frequency amplifier 62 and amplified to become the first intermediate frequency amplifier output which is a narrowband signal. 63
The first synchronous detector 24 uses the first synchronous detector 24 as a reference signal.
The signal is input to the synchronous detector 24.

The first power divider second output 45 is input to the second power divider 46 and becomes the second power divider first output 47 and the second power divider second output 49. The second power divider first output 47 is output to the second demodulator 56.
The demodulation signal 37 is demodulated as a demodulation signal and becomes the second demodulator output 57, which is then sent to the second intermediate frequency amplifier 6.
4 and becomes the second intermediate frequency amplifier output 65 which is a narrowband signal, and is input to the first synchronous detector 24 as a signal for error detection of the first synchronous detector 24 and is synchronously detected, which is necessary for synchronization. The first synchronous detector output 25 is an error signal.

The second power divider second output 49, which is the output of the second power divider 46, is input to the third power divider 50 and becomes the third power divider first output 51 and the third power divider output 53. The power divider first output 51 is demodulated in the third demodulator 58 using the third demodulation signal 39 as the demodulation signal to become the third demodulator output 59, which is input to the third intermediate frequency amplifier 66, amplified, and narrowed. Third intermediate frequency amplifier output 6 which is a band signal
7 and is input to the second synchronous detector 26 as a reference signal for the second synchronous detector 26.

The third power divider second output 53 is connected to the fourth demodulator 60
, the fourth demodulation signal 41 is demodulated as a demodulation signal to become a fourth demodulator output 61, which is input to a fourth intermediate frequency amplifier 68 and amplified to become a fourth intermediate frequency amplifier output 69 which is a narrowband signal. Second
The signal is input to the second synchronous detector 26 as a signal for detecting an error in the synchronous detector 26, is synchronously detected, and becomes the second synchronous detector output 27, which is an error signal necessary for synchronization.

The modulation/demodulation signal generator 70 shown in FIG. 2 is composed of a modulation signal generation section 70a and a demodulation signal generation section 70b. The first synchronous detector output 25 and the second synchronous detector output 27 are input to the demodulation signal generator 70b of the modulation/demodulation signal generator 70 and synchronized with the received signal 13. The first demodulation signal 75, which is a modulation signal for demodulation, and the second demodulation signal 75 are controlled in the demodulation signal generator 70b so that the output 27 of the two-synchronous detector becomes zero, and synchronization is maintained. A signal 77, a third signal for demodulation 79, and a fourth signal for demodulation 81 are created.

Local oscillator output 8 which is the output of local oscillator 82
3 is input to the hybrid circuit 84 and becomes the hybrid circuit first output 85 and the hybrid circuit second output 87, and one output of the hybrid circuit first output 85 is input to the third phase modulator 34 and becomes the first demodulation signal 75. is phase-modulated as a modulation signal to become a first demodulation signal 35, which becomes a demodulation signal for the first demodulator output 55.

Similarly, the other output of the hybrid circuit first output 85 is input to the fifth phase modulator 38 and is phase modulated using the third demodulation signal 79 as a modulation signal to become the third demodulation signal 39. This becomes a demodulation signal for output 59.

One output of the hybrid circuit second output 87 is input to the fourth phase modulator 36 and phase modulated using the second demodulation signal 77 as a modulation signal to become the second demodulation signal 37, and the second demodulator output 57 This becomes the demodulation signal for the

Similarly, the other output of the hybrid circuit second output 87 is input to the sixth phase modulator 40 and is phase modulated using the fourth demodulation signal 81 as a modulation signal to become the fourth demodulation signal 41. This becomes a demodulation signal for output 61.

A first intermediate frequency amplifier output 63 which is the output of the first intermediate frequency amplifier 62 and a second intermediate frequency amplifier 64
The second intermediate frequency amplifier output 65, which is the output of
It becomes the FFT analyzer output 89 and is used to detect the target signal.

The second embodiment shown in FIGS. 4 and 5 will be described. Only the parts that are different from FIG. 1 and FIG. 2 will be explained.

The first demodulation signal 35 is the output of the third phase modulator 34 and the second demodulation signal 35 is the output of the fourth phase modulator 36.
The demodulation signals 37 are respectively input to the second power combiner 90 and power-combined to become the first demodulation signal 35a or 35b, which is input to the first demodulator 54 as a demodulation signal, and is then output as the first output of the first power divider. 43
is demodulated and becomes the first demodulator output 55.

The third demodulation signal 39 is the output of the fifth phase modulator 38 and the fourth demodulation signal is the output of the sixth phase modulator 40.
The demodulation signals 41 are respectively input to a third power combiner 92 and power-combined to become a third demodulation signal 39a or 39b, which is input to a second demodulator 56 as a demodulation signal, and is then output as the second output of the first power divider. 45
is demodulated and becomes the second demodulator output 57.

The first synchronous detector output 25 is input to the demodulation signal generator 70b of the modulation/demodulation signal generator 70, and the first
The demodulation signal generator 70b controls the synchronization detector output 25 to zero, thereby maintaining synchronization.

(Supplementary Explanation) (A) In the embodiment shown in Figure 1, the intermediate frequency amplifier was explained as having four channels, but if time division is used, it is possible to make the intermediate frequency amplifier into two channels, in order to shorten the synchronization time. can expect the same effect.

(b) In the communication system, if the clock of the code sequence generator built in the modulation signal generator 70a of the modulation/demodulation signal generator 70 of the transmitter is phase-modulated or frequency-modulated, the first synchronous detector output 2 of the receiver
5 or the second synchronous detector output 27 can reproduce the modulated signal. Furthermore, if the clocks are modulated independently, two channels can be created.

(c) When the carrier wave is phase modulated [φ(t) or ψ(t)] or frequency modulated [φ(t) or ψ(t)], pass the intermediate frequency amplifier outputs (63 and 67) through a frequency discriminator. For example, phase modulated or frequency modulated signals can be demodulated. Furthermore, the modulated signal can be demodulated from the output of the synchronous detector of the synchronous loop.

(d) If the transmission signal is amplitude-modulated, an amplitude-modulated signal can be obtained from the intermediate frequency amplifier outputs (63 and 67), and the modulated signal can be demodulated.

(E) The transmission signal 11 may be pulse modulated or continuous wave modulated.

(f) In the embodiment shown in Figure 1, single super
Although the heterodyne method has been described, a double super-heterodyne method may also be used.

(g) The multiplicative detector of the embodiment shown in FIG. 1 may extract the error signal by an FFT detector realized by software using a digital FFT analyzer.

(H) The error signal obtained by the multiplicative detector output or FFT detection is E[η _aA (ωτ)ρ _aa (ωτ)]
,
E[η _aA (ωτ)] or E[η _aA (ωτ)/ρ _aa (
ωτ)]
Any error signal may be used.

(k) Show that sin (ω _i t) and cos (ω _i t) are functions of ω _i t.

(Effect of the invention) The effects of the present invention are as follows.

(a) In this system, the intermediate frequency amplifier output is an autocorrelation function of the received signal, so it is equivalent to configuring a matched filter, and this is a type of optimal receiver that achieves high-speed synchronization.

(b) When used in a communication system, there will be four independent channels, which corresponds to effective use of the transmission bandwidth.

(c) Since two types of pseudo-random signals (pseudo-random code sequences) are used, the unambiguous range of distance during distance measurement increases, making distance measurement easier.

(D) Since two types of pseudo-random signals (pseudo-random code sequences) are used, high-speed synchronization is possible and the target signal can be acquired in a short time.

(E) Since two types of pseudo-random signals (pseudo-random code sequences) are used, there is little possibility that the code sequence of the transmitted signal will be decoded, and the secrecy of the transmitted signal is extremely high.

(f) It is difficult to interfere with the intermediate frequency amplifier unless the transmitted signal is decrypted, so it is resistant to radio interference.

(g) Compared to the conventional multi-channel system for high-speed synchronization, a much greater effect of high-speed synchronization can be expected.

(h) According to the method related to the parts from formula (40) to formula (44) and the part from formula (45) to formula (49), the S-shaped characteristic of the disc discriminator can be made variable. Synchronous pull-in is easy.

(k) Having two types of pseudo-random signals (pseudo-random code sequences) makes it possible to concentrate the spectrum of one code sequence in the low range and the spectrum of the other code sequence in the high range. It is possible to simultaneously achieve broadband transmission to increase confidentiality and a wide pull-in width for synchronization.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of the main part of the first embodiment of the present invention, Fig. 2 is a block diagram of the remaining part of the first embodiment used in combination with the main part of Fig. 1, and Fig. 3 is a block diagram of the main part of the first embodiment of the present invention. The figure is a block diagram of the conventional example, Figure 4 is a block diagram of the main part of the second embodiment of the present invention, and Figure 5 is a block diagram of the main part of the second embodiment of the present invention.
This figure is a block diagram of the remaining part of the second embodiment used in combination with the main part of FIG. 4, and FIG. 6 is an explanatory diagram illustrating each signal in the first embodiment of the present invention. 10...Transmission antenna, 11...Transmission signal, 1
3...Received signal, 14...Receiving antenna, 15...
...Receiving antenna output, 16... Transmission source, 17...
Transmission source first output, 19... Transmission source second output, 20
... Power combiner, 21 ... Power combiner output, 22
...Transmitter, 23...Transmitter output, 24...First
Synchronous detector, 25...First synchronous detector output, 26
...Second synchronous detector, 27...Second synchronous detector output, 30...First phase modulator, 31...First phase modulator output, 32...Second phase modulator, 33...
Second phase modulator output, 34...Third phase modulator,
35... first demodulation signal, 35a... first demodulation signal, 35b... first demodulation signal, 36... fourth
Phase modulator, 37...Second demodulation signal, 38...
Fifth phase modulator, 39...Third demodulation signal, 39
a... Third demodulation signal, 39b... Third demodulation signal, 40... Sixth phase modulator, 41... Fourth demodulation signal, 42... First power divider, 43... First
Power divider first output, 45...First power divider second output, 46...Second power divider, 47...Second
Power divider first output, 49...Second power divider second output, 50...Third power divider, 51...Third
Power divider first output, 53... Third power divider second output, 54... First demodulator, 55... First demodulator output, 56... Second demodulator, 57... Second demodulation 58... Third demodulator, 59... Third demodulator output, 60... Fourth demodulator, 61... Fourth demodulator output, 62... First intermediate frequency amplifier, 63...
First intermediate frequency amplifier output, 64... Second intermediate frequency amplifier, 65... Second intermediate frequency amplifier output, 66
...Third intermediate frequency amplifier, 67...Third intermediate frequency amplifier output, 68...Fourth intermediate frequency amplifier, 69
... Fourth intermediate frequency amplifier output, 70 ... Modulation and demodulation signal generator, 70a ... Modulation signal generation section, 70
b...Demodulation signal generator, 71...First signal for modulation, 73...Second signal for modulation, 75...First signal for demodulation, 77...Second signal for demodulation, 79...For demodulation Third signal, 81...Fourth signal for demodulation, 82...
Local oscillator, 83... Local oscillator output, 84...
Hybrid circuit, 85...Hybrid circuit first output, 87...Hybrid circuit second output, 8
8...FFT analyzer, 89...FFT analyzer output,
90...Second power combiner, 92...Third power combiner, 110...Second transmission antenna, 111...Second transmission signal, 113...Second reception signal, 114...
...Second receiving antenna, 115...Second receiving antenna output, 116...Second transmission source, 117...Second
Transmission source output, 122...Second transmitter, 123...
Second transmitter output, 124...Third synchronous detector, 1
25... Third synchronous detector output, 130... Seventh phase modulator, 131... Seventh phase modulator output, 13
4...Eighth phase modulator, 135...Fifth demodulation signal, 136...Ninth phase modulator, 137...Sixth
Demodulation signal, 142...Fourth power divider, 143
...Fourth power divider first output, 145...Fourth power divider second output, 154...Fifth demodulator, 15
5...Fifth demodulator output, 156...Sixth demodulator,
157...Sixth demodulator output, 162...Fifth intermediate frequency amplifier, 163...Fifth intermediate frequency amplifier output, 164...Sixth intermediate frequency amplifier, 165...
Sixth intermediate frequency amplifier output, 170...Second modulation/demodulation signal generator, 171...Second modulation signal, 17
3...First signal for second demodulation, 175...Second signal for second demodulation, 182...Second local oscillator, 183
...Second local oscillator output, 190...Amplitude detector, 191...Amplitude detector output.

Claims (1)

[Claims] 1. A transmission source and a pseudo-random signal, a(t), having low cross-correlation between the transmission source output from the transmission source and the transmission source output from the transmission source.
and b(t) by phase modulation using different signals of one period, a(t) is created by two-phase quadrature modulation of 0, π, balanced quadrature modulation, or four-phase phase modulation. sin[ωt+φ(t)]+b(t) cos[ωt+
ψ
(t)] (where ω: angular frequency of carrier wave, φ(t) and ψ(t): terms due to phase modulation or frequency modulation); and a phase modulation means for creating a radio wave type signal; a transmitting antenna for transmitting a signal, a receiving antenna for receiving the radio wave type signal transmitted from the transmitting antenna, and a receiving antenna for demodulating the received signal of the receiving antenna, a(t), b(t),
Pseudo-random signal A(t) that is orthogonal to a(t)
and a pseudorandom signal B that is orthogonal to b(t)
(t) a demodulation signal generation unit that generates each signal;
a(t), b(t), A from the demodulation signal generator
a(t+τ)cos(ω _r t+α), A(t+τ)sin created from (t) and B(t)
(ω _r t + α), b (t + τ) sin (ω _r t + α) and B (t + τ) cos (ω _r t + α) (where, τ: synchronization shift, ω _r : angular frequency of demodulation signal, α: demodulation An intermediate frequency signal ρ _aa (τ) whose amplitude is the autocorrelation function or cross-correlation function is obtained by performing a multiplication operation with the received signal using each demodulation signal (an arbitrary phase of the signal) sin (ω _i t) + ρ _ba (τ) cos (ω _i t
), ρ _ab (τ) sin (ω _i t) + ρ _bb (τ) cos (ω _i t
), η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i t
) and η _aB (τ) sin (ω _i t) + η _bB (τ) cos (ω _i t
) (where ω _i =ω−ω _r , (ω _i t): a function of ω _i t), and further, their intermediate frequency signal ρ _aa (τ) sin (ω _i t) + ρ _ba ( τ) cos(ω _i t
) and η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i t
), and ρ _ab (τ) sin (ω _i t) + ρ _bb (τ) cos (ω _i t
) and η _aB (τ) sinf (ω _i t) + η _bB (τ) cosf (ω _i t)
and a detection means that performs multiplication detection or FFT detection, respectively, and the error signal obtained as the output of the detection means,
A synchronization device characterized in that the synchronization pull-in time is shortened and the period of the pseudo-random signal is effectively lengthened by feeding the signal back to the demodulation signal generation section. 2 The transmission source and the transmission source output from the transmission source are connected to each other by a pseudo-random signal with low cross-correlation, a(t)
and b(t) by phase modulation using different signals of one period, a(t) is created by two-phase quadrature modulation of 0, π, balanced quadrature modulation, or four-phase phase modulation. sin[ωt+φ(t)]+b(t) cos[ωt+
ψ
(t)] (where ω: angular frequency of carrier wave, φ(t) and ψ(t): terms due to phase modulation or frequency modulation); and a phase modulation means for creating a radio wave type signal; a(t), a demodulation signal generation unit that generates a pseudorandom signal A(t) that is orthogonal to b(t) and a(t), and a pseudorandom signal B(t) that is orthogonal to b(t); , a(t+τ)cos(ω _r t+α), A(t+τ)sin created from a(t), b(t), A(t) and B(t) from the demodulation signal generator.
(ω _r t + α), b (t + τ) sin (ω _r t + α) and B (t + τ) cos (ω _r t + α) (where, τ: synchronization shift, ω _r : angular frequency of demodulation signal, α: demodulation An intermediate frequency signal ρ _aa (τ) whose amplitude is the autocorrelation function or cross-correlation function is obtained by performing a multiplication operation with the received signal using each demodulation signal (an arbitrary phase of the signal) sin (ω _i t) + ρ _ba (τ) cos (ω _i t
), ρ _ab (τ) sin (ω _i t) + ρ _bb (τ) cos (ω _i t
), η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i t
) and η _aB (τ) sin (ω _i t) + η _bB (τ) cos (ω _i t
) (where ω _i =ω−ω _r , (ω _i t): a function of ω _i t), and further, their intermediate frequency signal ρ _aa (τ) sin (ω _i t) + ρ _ba ( τ) cos(ω _i t
) and η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i t
), and ρ _ab (τ) sin (ω _i t) + ρ _bb (τ) cos (ω _i t
) and η _aB (τ) sin (ω _i t) + η _bB (τ) cos (ω _i t
), and the error signal obtained as the output of the detection means is
A synchronizer that shortens the synchronization time by feeding back to the demodulation signal generator is used, and two types of pseudo-random signals, a(t) and b(t), are used. A radar that measures distance by reducing ambiguity in distance measurement by increasing the period of a transmission signal. 3 The transmission source and the transmission source output from the transmission source are connected to each other by a pseudorandom signal, a(t), with low cross-correlation.
and b(t) by phase modulation using different signals of one period, a(t) is created by two-phase quadrature modulation of 0, π, balanced quadrature modulation, or four-phase phase modulation. sin[ωt+φ(t)]+b(t) cos[ωt+
ψ
(t)] (where ω: angular frequency of carrier wave, φ(t) and ψ(t): terms due to phase modulation or frequency modulation); and a phase modulation means for creating a radio wave type signal; a transmitting antenna that transmits the signal to the receiving side, a receiving antenna that receives the radio wave type signal transmitted from the transmitting antenna, and a(t), b(t),
Pseudo-random signal A(t) that is orthogonal to a(t)
and a pseudorandom signal B that is orthogonal to b(t)
(t) a demodulation signal generation unit that generates each signal;
a(t), b(t), A from the demodulation signal generator
a(t+τ)cos(ω _r t+α), A(t+τ)sin created from (t) and B(t)
(ω _r t + α), b (t + τ) sin (ω _r t + α) and B (t + τ) cos (ω _r t + α) (where, τ: synchronization shift, ω _r : angular frequency of demodulation signal, α: demodulation An intermediate frequency signal ρ _aa (τ) whose amplitude is the autocorrelation function or cross-correlation function is obtained by performing a multiplication operation with the received signal using each demodulation signal (an arbitrary phase of the signal) sin (ω _i t) + ρ _ba (τ) cos (ω _i t
), ρ _ab (τ) sin (ω _i t) + ρ _bb (τ) cos (ω _i t
), η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i t
) and η _aB (τ) sin (ω _i t) + η _bB (τ) cos (ω _i t
) (where ω _i =ω−ω _r , (ω _i t): a function of ω _i t), and further, their intermediate frequency signal ρ _aa (τ) sin (ω _i t) + ρ _ba ( τ) cos(ω _i t
) and η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i t
), and ρ _ab (τ) sin (ω _i t) + ρ _bb (τ) cos (ω _i t
) and η _aB (τ) sin (ω _i t) + η _bB (τ) cos (ω _i t
), and the error signal obtained as the output of the detection means is
Demodulating the modulated signal φ(t) or ψ(t) of the intermediate frequency signal using a synchronizer that shortens the synchronization pull-in time by feeding it back to the demodulation signal generator. The modulated signal is demodulated using a frequency discriminator, the modulated signal is demodulated from the output of the detection means, or the amplitude modulated signal of the intermediate frequency signal is demodulated by amplitude detection. communication equipment. 4 The transmission source and the transmission source output from the transmission source are connected to each other by a pseudo-random signal with low cross-correlation, a(t)
A(t) is created by phase modulation using equal signals of one period of and b(t), by two-phase quadrature modulation of 0, π, balanced quadrature modulation, or four-phase phase modulation. sin[ωt+φ(t)]+b(t) cos[ωt+
ψ
(t)] (where ω: angular frequency of carrier wave, φ(t) and ψ(t): terms due to phase modulation or frequency modulation); and a phase modulation means for creating a radio wave type signal; a transmitting antenna for transmitting a signal, a receiving antenna for receiving the radio wave type signal transmitted from the transmitting antenna, and a receiving antenna for demodulating the received signal of the receiving antenna, a(t), b(t),
Pseudo-random signal A(t) that is orthogonal to a(t)
and a pseudorandom signal B that is orthogonal to b(t)
(t) a demodulation signal generation unit that generates each signal;
a(t), b(t), A from the demodulation signal generator
a(t+τ)cos(ω _r t+α), A(t+τ)sin created from (t) and B(t)
(ω _r t + α), b (t + τ) sin (ω _r t + α) and B (t + τ) cos (ω _r t + α) (where, τ: synchronization shift, ω _r : angular frequency of demodulation signal, α: demodulation An intermediate frequency signal ρ _aa (τ) whose amplitude is the autocorrelation function or cross-correlation function is obtained by performing a multiplication operation with the received signal using each demodulation signal (an arbitrary phase of the signal) sin (ω _i t) + ρ _ba (τ) cos (ω _i t
), ρ _ab (τ) sin (ω _i t) + ρ _bb (τ) cos (ω _i t
), η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i t
) and η _aB (τ) sin (ω _i t) + η _bB (τ) cos (ω _i t
) (where ω _i =ω−ω _r , (ω _i t): a function of ω _i t), and further, their intermediate frequency signal ρ _aa (τ) sin (ω _i t) + ρ _ba ( τ) cos(ω _i t
) and η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i t
), and ρ _ab (τ) sin (ω _i t) + ρ _bb (τ) cos (ω _i t
) and η _aB (τ) sin (ω _i t) + η _bB (τ) cos (ω _i t
), and the error signal obtained as the output of the detection means is
Synchronization is performed by feeding back the signal to the demodulation signal generator, and at the same time, the pseudo-random signal a
When the bit length of (t) is a, the number of bits is M, the bit length of pseudorandom signal b(t) is b, and the number of bits is N, the relationship aM = bN is established and the S-shaped characteristic of the error signal is determined. A synchronizing device characterized by being able to make variable. 5 A transmission source and a transmission source output from the transmission source are connected to each other by a pseudo-random signal with low cross-correlation, a(t)
A(t) is created by phase modulation using equal signals of one period of and b(t), by two-phase quadrature modulation of 0, π, balanced quadrature modulation, or four-phase phase modulation. sin[ωt+φ(t)]+b(t)cos[ωt+
ψ
(t)] (where ω: angular frequency of carrier wave, φ(t) and ψ(t): terms due to phase modulation or frequency modulation); and a phase modulation means for creating a radio wave type signal; a(t), a demodulation signal generation unit that generates a pseudorandom signal A(t) that is orthogonal to b(t) and a(t), and a pseudorandom signal B(t) that is orthogonal to b(t); , a(t+τ)cos(ω _r t+α), A(t+τ)sin created from a(t), b(t), A(t) and B(t) from the demodulation signal generator.
(ω _r t + α), b (t + τ) sin (ω _r t + α) and B (t + τ) cos (ω _r t + α) (where, τ: synchronization shift, ω _r : angular frequency of demodulation signal, α: demodulation An intermediate frequency signal ρ _aa (τ) whose amplitude is the autocorrelation function or cross-correlation function is obtained by performing a multiplication operation with the received signal using each demodulation signal (an arbitrary phase of the signal) sin (ω _i t) + ρ _ba (τ) cos (ω _i t
), ρ _ab (τ) sin (ω _i t) + ρ _bb (τ) cos (ω _i t
), η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i t
) and η _aB (τ) sin (ω _i t) + η _bB (τ) cos (ω _i t
) (however, ω _i =ω−ω _r , f(ω _i t): a function of ω _i t), and further, their intermediate frequency signal ρ _aa (τ) sin (ω _i t) + ρ _ba (τ)cos(ω _i t
) and η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i t
), and ρ _ab (τ) sin (ω _i t) + ρ _bb (τ) cos (ω _i t
) and η _aB (τ) sin (ω _i t) + η _bB (τ) cos (ω _i t
), and the error signal obtained as the output of the detection means is
Synchronization is performed by feeding back the signal to the demodulation signal generator, and at the same time, the pseudo-random signal a
When the bit length of (t) is a, the number of bits is M, the bit length of pseudorandom signal b(t) is b, and the number of bits is N, the relationship aM = bN is established and the S-shaped characteristic of the error signal is determined. A radar characterized in that it uses a synchronization device that can make the synchronization variable, and performs distance measurement by facilitating synchronization pull-in. 6 A transmission source and a transmission source output from the transmission source are connected to each other by a pseudo-random signal with low cross-correlation, a(t)
A(t) is created by phase modulation using equal signals of one period of and b(t), by two-phase quadrature modulation of 0, π, balanced quadrature modulation, or four-phase phase modulation. sin[ωt+φ(t)]+b(t) cos[ωt+
ψ
(t)] (where ω: angular frequency of carrier wave, φ(t) and ψ(t): terms due to phase modulation or frequency modulation); and a phase modulation means for creating a radio wave type signal; a transmitting antenna that transmits the signal to the receiving side, a receiving antenna that receives the radio wave type signal transmitted from the transmitting antenna, and a(t), b(t),
Pseudo-random signal A(t) that is orthogonal to a(t)
and a pseudorandom signal B that is orthogonal to b(t)
(t) a demodulation signal generation unit that generates each signal;
a(t), b(t), A from the demodulation signal generator
a(t+τ)cos(ω _r t+α), A(t+τ)sin created from (t) and B(t)
(ω _r t + α), b (t + τ) sin (ω _r t + α) and B (t + τ) cos (ω _r t + α) (where, τ: synchronization shift, ω _r : angular frequency of demodulation signal, α: demodulation An intermediate frequency signal ρ _aa (τ) whose amplitude is the autocorrelation function or cross-correlation function is obtained by performing a multiplication operation with the received signal using each demodulation signal (an arbitrary phase of the signal) sin (ω _i t) + ρ _ba (τ) cos (ω _i t
), ρ _ab (τ) sin (ω _i t) + ρ _bb (τ) cos (ω _i t
), η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i t
) and η _aB (τ) sin (ω _i t) + η _bB (τ) cos (ω _i t
) (where ω _i =ω−ω _r , (ω _i t): a function of ω _i t), and further, their intermediate frequency signal ρ _aa (τ) sin (ω _i t) + ρ _ba ( τ) cos(ω _i t
) and η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i t
), and ρ _ab (τ) sin (ω _i t) + ρ _bb (τ) cos (ω _i t
) and η _aB (τ) sin (ω _i t) + η _bB (τ) cos (ω _i t
), and the error signal obtained as the output of the detection means is
Synchronization is performed by feeding back the signal to the demodulation signal generator, and at the same time, the pseudo-random signal a
When the bit length of (t) is a, the number of bits is M, the bit length of pseudorandom signal b(t) is b, and the number of bits is N, the relationship aM = bN is established and the S-shaped characteristic of the error signal is determined. A synchronizing device capable of making the frequency variable is used to facilitate synchronization pull-in, and a frequency discriminator is used to demodulate the modulated signal φ(t) or ψ(t) of the intermediate frequency signal. The communication device is characterized in that the modulated signal is demodulated from the output of the detection means, or the amplitude modulated signal of the intermediate frequency signal is amplitude-detected and demodulated. 7 The transmission source and the transmission source output from the transmission source are connected to each other by a pseudo-random signal with low cross-correlation, a(t)
and b(t) by phase modulation using different signals of one period, a(t) is created by two-phase quadrature modulation of 0, π, balanced quadrature modulation, or four-phase phase modulation. sin[ωt+φ(t)]+b(t) cos[ωt+
ψ
(t)] (where ω: angular frequency of carrier wave, φ(t) and ψ(t): terms due to phase modulation or frequency modulation); and a phase modulation means for creating a radio wave type signal; a transmitting antenna for transmitting a signal, a receiving antenna for receiving the radio wave type signal transmitted from the transmitting antenna, and a(t), b(t),
Pseudo-random signal A(t) that is orthogonal to a(t)
and a pseudorandom signal B that is orthogonal to b(t)
(t) a demodulation signal generation unit that generates each signal;
a(t), b(t), A from the demodulation signal generator
a(t+τ)cos(ω _r t+α)+b(t+τ)sin created from (t) and B(t)
(ω _r t+α) and A(t+τ) cos(ω _r t+α)+B(t+τ) sin
(ω _r t + α) (where τ: synchronization difference, ω _r : angular frequency of the demodulating signal, α: arbitrary phase of the demodulating signal) _By performing the _{multiplication operation with}
t)+
ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)
] and [η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
] (however, ω _i =ω−ω _r , (ω _i t): a function of ω _i t), and their intermediate frequency signal [ρ _aa (τ) sin (ω _i t) + ρ _ba (τ)cos(ω _i
t)+
ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)
] and [η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
], and detecting means for performing multiplication detection or FFT detection of
A synchronization device characterized in that the synchronization pull-in time is shortened and the period of the pseudo-random signal is effectively lengthened by feeding the signal back to the demodulation signal generation section. 8 A transmission source and a transmission source output from the transmission source are connected to each other by a pseudo-random signal with low cross-correlation, a(t)
and b(t) by phase modulation using different signals of one period, a(t) is created by two-phase quadrature modulation of 0, π, balanced quadrature modulation, or four-phase phase modulation. sin[ωt+φ(t)]+b(t) cos[ωt+
ψ
(t)] (where ω: angular frequency of carrier wave, φ(t) and ψ(t): terms due to phase modulation or frequency modulation); and a phase modulation means for creating a radio wave type signal; a(t), a demodulation signal generation unit that generates a pseudorandom signal A(t) that is orthogonal to b(t) and a(t), and a pseudorandom signal B(t) that is orthogonal to b(t); , a(t+τ)cos(ω _r t+α)+b(t+τ)sin created from a(t), b(t), A(t) and B(t) from the demodulation signal generator.
(ω _r t+α) and A(t+τ) cos(ω _r t+α)+B(t+τ) sin
(ω _r t + α) (where τ: synchronization difference, ω _r : angular frequency of the demodulating signal, α: arbitrary phase of the demodulating signal) _By performing the _{multiplication operation with}
t)+
ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)
] and [η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
] (however, ω _i =ω−ω _r , (ω _i t): a function of ω _i t), and their intermediate frequency signal [ρ _aa (τ) sin (ω _i t) + ρ _ba (τ)cos(ω _i
t+ρ _ab
(τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)] and [η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
], and detecting means for performing multiplication detection or FFT detection of
A synchronizer that shortens the synchronization time by feeding back to the demodulation signal generator is used, and two types of pseudo-random signals, a(t) and b(t), are used. A radar that measures distance by reducing ambiguity in distance measurement by increasing the period of a transmission signal. 9 A transmission source and a transmission source output from the transmission source are connected to each other by a pseudo-random signal with low cross-correlation, a(t)
and b(t) by phase modulation using different signals of one period, a(t) is created by two-phase quadrature modulation of 0, π, balanced quadrature modulation, or four-phase phase modulation. sin[ωt+φ(t)]+b(t) cos[ωt+
ψ
(t)] (where ω: angular frequency of carrier wave, φ(t) and ψ(t): terms due to phase modulation or frequency modulation); and a phase modulation means for creating a radio wave type signal; a transmitting antenna that transmits the signal to the receiving side, a receiving antenna that receives the radio wave type signal transmitted from the transmitting antenna, and a(t), b(t),
Pseudo-random signal A(t) that is orthogonal to a(t)
and a pseudorandom signal B that is orthogonal to b(t)
(t) a demodulation signal generation unit that generates each signal;
a(t), b(t), A from the demodulation signal generator
a(t+τ)cos(ω _r t+α)+b(t+τ)sin created from (t) and B(t)
(ω _r t+α) and A(t+τ) cos(ω _r t+α)+B(t+τ) sin
(ω _r t + α) (where τ: synchronization difference, ω _r : angular frequency of the demodulating signal, α: arbitrary phase of the demodulating signal) _By performing the _{multiplication operation with}
t)+
ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)
] and [η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
] (however, ω _i =ω−ω _r , (ω _i t): a function of ω _i t), and their intermediate frequency signal [ρ _aa (τ) sin (ω _i t) + ρ _ba (τ)cos(ω _i
t)+
ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)
] and [η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
], and detecting means for performing multiplication detection or FFT detection of
Demodulating the modulated signal φ(t) or ψ(t) of the intermediate frequency signal using a synchronizer that shortens the synchronization pull-in time by feeding it back to the demodulation signal generator. The modulated signal is demodulated using a frequency discriminator, the modulated signal is demodulated from the output of the detection means, or the amplitude modulated signal of the intermediate frequency signal is demodulated by amplitude detection. communication equipment. 10 A transmission source and a pseudorandom signal, a(t), which has a low cross-correlation between the transmission source output from the transmission source and the transmission source output from the transmission source.
A(t) is created by phase modulation using equal signals of one period of and b(t), by two-phase quadrature modulation of 0, π, balanced quadrature modulation, or four-phase phase modulation. sin[ωt+φ(t)]+b(t) cos[ωt+
ψ
(t)] (where ω: angular frequency of carrier wave, φ(t) and ψ(t): terms due to phase modulation or frequency modulation); and a phase modulation means for creating a radio wave type signal; a transmitting antenna for transmitting a signal, a receiving antenna for receiving the radio wave type signal transmitted from the transmitting antenna, and a receiving antenna for demodulating the received signal of the receiving antenna, a(t), b(t),
Pseudo-random signal A(t) that is orthogonal to a(t)
and a pseudorandom signal B that is orthogonal to b(t)
(t) a demodulation signal generation unit that generates each signal;
a(t), b(t), A from the demodulation signal generator
a(t+τ)cos(ω _r t+α)+b(t+τ)sin created from (t) and B(t)
(ω _r t+α) and A(t+τ) cos(ω _r t+α)+B(t+τ) sin
(ω _r t + α) (where τ: synchronization difference, ω _r : angular frequency of the demodulating signal, α: arbitrary phase of the demodulating signal) _By performing the _{multiplication operation with}
t)+
ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)
] and [η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
] (however, ω _i =ω−ω _r , (ω _i t): a function of ω _i t), and their intermediate frequency signal [ρ _aa (τ) sin (ω _i t) + ρ _ba (τ)cos(ω _i
t)+
ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)
] and [η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
], and detecting means for performing multiplication detection or FFT detection of
Synchronization is performed by feeding back the signal to the demodulation signal generator, and at the same time, the pseudo-random signal a
When the bit length of (t) is a, the number of bits is M, the bit length of pseudorandom signal b(t) is b, and the number of bits is N, the relationship aM = bN is established and the S-shaped characteristic of the error signal is determined. A synchronizing device characterized by being able to make variable. 11 The transmission source and the transmission source output from the transmission source are connected to each other by a pseudo-random signal with low cross-correlation, a(t)
A(t) is created by phase modulation using equal signals of one period of and b(t), by two-phase quadrature modulation of 0, π, balanced quadrature modulation, or four-phase phase modulation. sin[ωt+φ(t)]+b(t) cos[ωt+
ψ
(t)] (where ω: angular frequency of carrier wave, φ(t) and ψ(t): terms due to phase modulation or frequency modulation); and a phase modulation means for creating a radio wave type signal; a(t), a demodulation signal generation unit that generates a pseudorandom signal A(t) that is orthogonal to b(t) and a(t), and a pseudorandom signal B(t) that is orthogonal to b(t); , a(t+τ)cos(ω _r t+α)+b(t+τ)sin created from a(t), b(t), A(t) and B(t) from the demodulation signal generator.
(ω _r t+α) and A(t+τ) cos(ω _r t+α)+B(t+τ) sin
(ω _r t + α) (where τ: synchronization difference, ω _r : angular frequency of the demodulating signal, α: arbitrary phase of the demodulating signal) _By performing the _{multiplication operation with}
t)+
ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)
] and [η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
] (however, ω _i =ω−ω _r , (ω _i t): a function of ω _i t), and their intermediate frequency signal [ρ _aa (τ) sin (ω _i t) + ρ _ba (τ)cos(ω _i
t)+
ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)
] and [η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
], and detecting means for performing multiplication detection or FFT detection of
Synchronization is performed by feeding back the signal to the demodulation signal generator, and at the same time, the pseudo-random signal a
When the bit length of (t) is a, the number of bits is M, the bit length of pseudorandom signal b(t) is b, and the number of bits is N, the relationship aM = bN is established and the S-shaped characteristic of the error signal is determined. A radar characterized in that it uses a synchronization device that can make the synchronization variable, and performs distance measurement by facilitating synchronization pull-in. 12 A transmission source and a transmission source output from the transmission source are connected to each other by a pseudo-random signal with low cross-correlation, a(t)
A(t) is created by phase modulation using equal signals of one period of and b(t), by two-phase quadrature modulation of 0, π, balanced quadrature modulation, or four-phase phase modulation. sin[ωt+φ(t)]+b(t) cos[ωt+
ψ
(t)] (where ω: angular frequency of carrier wave, φ(t) and ψ(t): terms due to phase modulation or frequency modulation); and a phase modulation means for creating a radio wave type signal; a transmitting antenna that transmits the signal to the receiving side, a receiving antenna that receives the radio wave type signal transmitted from the transmitting antenna, and a(t), b(t),
Pseudo-random signal A(t) that is orthogonal to a(t)
and a pseudorandom signal B that is orthogonal to b(t)
(t) a demodulation signal generation unit that generates each signal;
a(t), b(t), A from the demodulation signal generator
a(t+τ)cos(ω _r t+α)+b(t+τ)sin created from (t) and B(t)
(ω _r t+α) and A(t+τ) cos(ω _r t+α)+B(t+τ) sin
(ω _r t + α) (where τ: synchronization difference, ω _r : angular frequency of the demodulating signal, α: arbitrary phase of the demodulating signal) _By performing the _{multiplication operation with}
t)+
ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)
] and [η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
] (however, ω _i =ω−ω _r , (ω _i t): a function of ω _i t), and their intermediate frequency signal [ρ _aa (τ) sin (ω _i t) + ρ _ba (τ)cos(ω _i
t)+
ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)
] and [η _aA (τ) sin (ω _i t) + η _bA (τ) cos (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
], and detecting means for performing multiplication detection or FFT detection of
Synchronization is performed by feeding back the signal to the demodulation signal generator, and at the same time, the pseudo-random signal a
When the bit length of (t) is a, the number of bits is M, the bit length of pseudorandom signal b(t) is b, and the number of bits is N, the relationship aM = bN is established and the S-shaped characteristic of the error signal is determined. A synchronizing device capable of making the frequency variable is used to facilitate synchronization pull-in, and a frequency discriminator is used to demodulate the modulated signal φ(t) or ψ(t) of the intermediate frequency signal. A communication device characterized in that the modulated signal is demodulated from the output of the detection means, or the amplitude modulated signal of the intermediate frequency signal is amplitude-detected and demodulated. 13 A transmission source and a transmission source output from the transmission source are connected to each other by a pseudo-random signal with low cross-correlation, a(t)
and b(t) by phase modulation using different signals of one period, a(t) is created by two-phase quadrature modulation of 0, π, balanced quadrature modulation, or four-phase phase modulation. sin[ωt+φ(t)]+b(t) cos[ωt+
ψ
(t)] (where ω: angular frequency of carrier wave, φ(t) and ψ(t): terms due to phase modulation or frequency modulation); and a phase modulation means for creating a radio wave type signal; a transmitting antenna for transmitting a signal, a receiving antenna for receiving the radio wave type signal transmitted from the transmitting antenna, and a receiving antenna for demodulating the received signal of the receiving antenna, a(t), b(t),
Pseudo-random signal A(t) that is orthogonal to a(t)
and a pseudorandom signal B that is orthogonal to b(t)
(t) a demodulation signal generation unit that generates each signal;
a(t), b(t), A from the demodulation signal generator
a(t+τ) sin(ω _r t+α)+b(t+τ) sin created from (t) and B(t)
(ω _r t+α) and A(t+τ) sin(ω _r t+α)+B(t+τ) sin
(ω _r t + α) (where τ: synchronization difference, ω _r : angular frequency of the demodulating signal, α: arbitrary phase of the demodulating signal) _By performing the _{multiplication operation with}
t)+
ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)
] and [η _aA (τ) cos (ω _i t) + η _bA (τ) sin (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
] (however, ω _i =ω−ω _r , (ω _i t): a function of ω _i t), and further their intermediate frequency signal [ρ _aa (τ) cos (ω _i t) + ρ _ba (τ) sin(ω _i
t)+
ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)
] and [η _aA (τ) cos (ω _i t) + η _bA (τ) sin (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
], and detecting means for performing multiplication detection or FFT detection of
A synchronization device characterized in that the synchronization pull-in time is shortened and the period of the pseudo-random signal is effectively lengthened by feeding the signal back to the demodulation signal generation section. 14 A transmission source and a transmission source output from the transmission source are connected to each other by a pseudo-random signal with low cross-correlation, a(t)
and b(t) by phase modulation using different signals of one period, a(t) is created by two-phase quadrature modulation of 0, π, balanced quadrature modulation, or four-phase phase modulation. sin[ωt+φ(t)]+b(t) cos[ωt+
ψ
(t)] (where ω: angular frequency of carrier wave, φ(t) and ψ(t): terms due to phase modulation or frequency modulation); and a phase modulation means for creating a radio wave type signal; a(t), a demodulation signal generation unit that generates a pseudorandom signal A(t) that is orthogonal to b(t) and a(t), and a pseudorandom signal B(t) that is orthogonal to b(t); , a(t+τ)sin(ω _r t+α)+b(t+τ)sin created from a(t), b(t), A(t) and B(t) from the demodulation signal generator.
(ω _r t+α) and A(t+τ) sin(ω _r t+α)+B(t+τ) sin
(ω _r t + α) (where τ: synchronization shift, ω _r : angular frequency of the demodulating signal, α: arbitrary phase of the demodulating signal) _By performing the _{multiplication operation with}
t)+
ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)
] and [η _aA (τ) cos (ω _i t) + η _bA (τ) sin (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
] (however, ω _i =ω−ω _r , (ω _i t): a function of ω _i t), and their intermediate frequency signal [ρ _aa (τ) cos (ω _i t) + ρ _ba (τ) sin(ω _i
t)+
ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)
] and [η _aA (τ) cos (ω _i t) + η _bA (τ) sin (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
], and detecting means for performing multiplication detection or FFT detection of
A synchronizer that shortens the synchronization time by feeding back to the demodulation signal generator is used, and two types of pseudo-random signals, a(t) and b(t), are used. A radar that measures distance by reducing ambiguity in distance measurement by increasing the period of a transmission signal. 15 The transmission source and the transmission source output from the transmission source are connected to each other by a pseudo-random signal with low cross-correlation, a(t)
and b(t) by phase modulation using different signals of one period, a(t) is created by two-phase quadrature modulation of 0, π, balanced quadrature modulation, or four-phase phase modulation. sin[ωt+φ(t)]+b(t) cos[ωt+
ψ
(t)] (where ω: angular frequency of carrier wave, φ(t) and ψ(t): terms due to phase modulation or frequency modulation); and a phase modulation means for creating a radio wave type signal; a transmitting antenna that transmits the signal to the receiving side, a receiving antenna that receives the radio wave type signal transmitted from the transmitting antenna, and a(t), b(t),
Pseudo-random signal A(t) that is orthogonal to a(t)
and a pseudorandom signal B that is orthogonal to b(t)
(t) a demodulation signal generation unit that generates each signal;
a(t), b(t), A from the demodulation signal generator
a(t+τ) sin(ω _r t+α)+b(t+τ) sin created from (t) and B(t)
(ω _r t+α) and A(t+τ) sin(ω _r t+α)+B(t+τ) sin
(ω _r t + α) (where τ: synchronization difference, ω _r : angular frequency of the demodulating signal, α: arbitrary phase of the demodulating signal) _By performing the _{multiplication operation with}
t)+
ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)
] and [η _aA (τ) cos (ω _i t) + η _bA (τ) sin (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
] (however, ω _i =ω−ω _r , (ω _i t): a function of ω _i t), and further their intermediate frequency signal [ρ _aa (τ) cos (ω _i t) + ρ _ba (τ) sin(ω _i
t)+
ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)
] and [η _aA (τ) cos (ω _i t) + η _bA (τ) sin (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
], and detecting means for performing multiplication detection or FFT detection of
Demodulating the modulated signal φ(t) or ψ(t) of the intermediate frequency signal using a synchronizer that shortens the synchronization pull-in time by feeding it back to the demodulation signal generator. The modulated signal is demodulated using a frequency discriminator, the modulated signal is demodulated from the output of the detection means, or the amplitude modulated signal of the intermediate frequency signal is demodulated by amplitude detection. communication equipment. 16 A transmission source and a transmission source output from the transmission source are connected to each other by a pseudo-random signal with low cross-correlation, a(t)
A(t) is created by phase modulation using equal signals of one period of and b(t), by two-phase quadrature modulation of 0, π, balanced quadrature modulation, or four-phase phase modulation. sin[ωt+φ(t)]+b(t) cos[ωt+
ψ
(t)] (where ω: angular frequency of carrier wave, φ(t) and ψ(t): terms due to phase modulation or frequency modulation); and a phase modulation means for creating a radio wave type signal; a transmitting antenna for transmitting a signal, a receiving antenna for receiving the radio wave type signal transmitted from the transmitting antenna, and a receiving antenna for demodulating the received signal of the receiving antenna, a(t), b(t),
Pseudo-random signal A(t) that is orthogonal to a(t)
and a pseudorandom signal B that is orthogonal to b(t)
(t) a demodulation signal generation unit that generates each signal;
a(t), b(t), A from the demodulation signal generator
a(t+τ) sin(ω _r t+α)+b(t+τ) sin created from (t) and B(t)
(ω _r t+α) and A(t+τ) sin(ω _r t+α)+B(t+τ) sin
(ω _r t + α) (where τ: synchronization difference, ω _r : angular frequency of the demodulating signal, α: arbitrary phase of the demodulating signal) _By performing the _{multiplication operation with}
t)+
ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)
] and [η _aA (τ) cos (ω _i t) + η _bA (τ) sin (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
] (however, ω _i =ω−ω _r , (ω _i t): a function of ω _i t), and further their intermediate frequency signal [ρ _aa (τ) cos (ω _i t) + ρ _ba (τ) sin(ω _i
t)+
ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)
] and [η _aA (τ) cos (ω _i t) + η _bA (τ) sin (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
], and detecting means for performing multiplication detection or FFT detection of
Synchronization is performed by feeding back the signal to the demodulation signal generator, and at the same time, the pseudo-random signal a
When the bit length of (t) is b and the number of bits is N,
A synchronization device characterized in that the S-shaped characteristic of the error signal can be varied by establishing the relationship aM=bN. 17 The transmission source and the transmission source output from the transmission source are connected to each other by a pseudo-random signal with low cross-correlation, a(t)
A(t) is created by phase modulation using equal signals of one period of and b(t), by two-phase quadrature modulation of 0, π, balanced quadrature modulation, or four-phase phase modulation. sin[ωt+φ(t)]+b(t) cos[ωt+
ψ
(t)] (where ω: angular frequency of carrier wave, φ(t) and ψ(t): terms due to phase modulation or frequency modulation); and a phase modulation means for creating a radio wave type signal; a(t), a demodulation signal generation unit that generates a pseudorandom signal A(t) that is orthogonal to b(t) and a(t), and a pseudorandom signal B(t) that is orthogonal to b(t); , a(t+τ)sin(ω _r t+α)+b(t+τ)sin created from a(t), b(t), A(t) and B(t) from the demodulation signal generator.
(ω _r t+α) and A(t+τ) sin(ω _r t+α)+B(t+τ) sin
(ω _r t + α) (where τ: synchronization difference, ω _r : angular frequency of the demodulating signal, α: arbitrary phase of the demodulating signal) _By performing the _{multiplication operation with}
t)+
ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)
] and [η _aA (τ) cos (ω _i t) + η _bA (τ) sin (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
] (however, ω _i =ω−ω _r , (ω _i t): a function of ω _i t), and further their intermediate frequency signal [ρ _aa (τ) cos (ω _i t) + ρ _ba (τ) sin(ω _i
t)+
ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)
] and [η _aA (τ) cos (ω _i t) + η _bA (τ) sin (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
], and detecting means for performing multiplication detection or FFT detection of
Synchronization is performed by feeding back the signal to the demodulation signal generator, and at the same time, the pseudo-random signal a
When the bit length of (t) is a, the number of bits is M, the bit length of pseudorandom signal b(t) is b, and the number of bits is N, the relationship aM = bN is established and the S-shaped characteristic of the error signal is determined. A radar characterized in that it uses a synchronization device that can make the synchronization variable, and performs distance measurement by facilitating synchronization pull-in. 18 A transmission source and a transmission source output from the transmission source are connected to each other by a pseudo-random signal with low cross-correlation, a(t)
A(t) is created by phase modulation using equal signals of one period of and b(t), by two-phase quadrature modulation of 0, π, balanced quadrature modulation, or four-phase phase modulation. sin[ωt+φ(t)]+b(t) cos[ωt+
ψ
(t)] (where ω: angular frequency of carrier wave, φ(t) and ψ(t): terms due to phase modulation or frequency modulation); and a phase modulation means for creating a radio wave type signal; a transmitting antenna that transmits the signal to the receiving side, a receiving antenna that receives the radio wave type signal transmitted from the transmitting antenna, and a(t), b(t),
Pseudo-random signal A(t) that is orthogonal to a(t)
and a pseudorandom signal B that is orthogonal to b(t)
(t) a demodulation signal generation unit that generates each signal;
a(t), b(t), A from the demodulation signal generator
a(t+τ) sin(ω _r t+α)+b(t+τ) sin created from (t) and B(t)
(ω _r t+α) and A(t+τ) sin(ω _r t+α)+B(t+τ) sin
(ω _r t + α) (where τ: synchronization shift, ω _r : angular frequency of the demodulating signal, α: arbitrary phase of the demodulating signal) _By performing the _{multiplication operation with}
t)+
ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)
] and [η _aA (τ) cos (ω _i t) + η _bA (τ) sin (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
] (however, ω _i =ω−ω _r , (ω _i t): a function of ω _i t), and their intermediate frequency signal [ρ _aa (τ) cos (ω _i t) + ρ _ba (τ) sin(ω _i
t)+
ρ _ab (τ) cos (ω _i t) + ρ _bb (τ) sin (ω _i t)
] and [η _aA (τ) cos (ω _i t) + η _bA (τ) sin (ω _i
t)+
η _aB (τ) cos (ω _i t) + η _bB (τ) sin (ω _i t)
] is provided with a detection means for performing multiplication detection or FFT detection respectively, and the error signal obtained as the output of the detection means is
Synchronization is performed by feeding back the signal to the demodulation signal generator, and at the same time, the pseudo-random signal a
When the bit length of (t) is a, the number of bits is M, the bit length of pseudorandom signal b(t) is b, and the number of bits is N, the relationship aM = bN is established and the S-shaped characteristic of the error signal is determined. A synchronizing device capable of making the frequency variable is used to facilitate synchronization pull-in, and a frequency discriminator is used to demodulate the modulated signal φ(t) or ψ(t) of the intermediate frequency signal. The communication device is characterized in that the modulated signal is demodulated from the output of the detection means, or the amplitude modulated signal of the intermediate frequency signal is amplitude-detected and demodulated.