JPH01115202A - Information transmitting system - Google Patents

Abstract

PURPOSE:To halve an occupied band width by using the phase relation of a side band wave in which an FM wave and an AM wave occur due to the same modulating wave and removing an upper or lower side band wave component. CONSTITUTION:In MEMO, one period part of a sine wave is stored in which an instantaneous frequency value to be transmitted beforehand is fmA and an amplitude is Am. Namely, Am=2AoJ1(mf) is obtained. Here, when a 16-acid ASCII data value is Dx, J1(mf)=KDx is obtained, and therefore, Am=2AoKDx is obtained. The waveform becomes the one to cancel and remove the upper side band wave as shown in the figure. Namely, when an ASCII code to be transmitted does not exist, the sine wave of an instantaneous frequency Fc and an amplitude Ao, which are a central frequency, is obtained, and when an ASCII code T to be transmitted appears, the sine wave, which is fmT=Fc-55 Hz and AmT=2AoKD4, is outputted for one period. Thus, by canceling and removing the upper or lower side band wave component, the occupied bandwave width can be halved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in an information transmission method using pulsed waves of multi-frequency values (Showa & Q, Mochiju I No. 282613, Information Transmission Method #Reference). In carrying out multiplex communication using a frequency division method or the like using a transmission line of the same width as the present invention, a manual method is provided to reduce the transmission line usage efficiency to 1 (f&large).

b) The current value iFM of the FM output wave can be calculated using the following equation.

iFM w IOsin (ωOt −mf cosl
Jt )=s ko (JO(mf) Sin ωO
t-Jl (mf) (aos (ω0+ta) to 10 cos(ωO-ω)t) -J2 (mr) (-----)-----------
---) At this time, if mf is less than 0.3, there is no @band component higher than the second sideband (lower than Eme).Therefore, sidebands are generated only at the two points of fo + f. It is well known that this will happen.

That is, when mf is always Q, 3 and ti (this type), J 躬 becomes the above formula.

iJM-IO[Jo (mf) 5in(UOt+
Jl (mf) (cos (uJo + (Ll)
10 cos(ω0-ω)t)] -------1 formula.

0) On the other hand, the i current of the AM output wave @ iAM l can be expressed in Table 1 using the following equation.

iAM w IO(1,+m 9in CIJ t'
) 91nuJOtw! 0(gi, nωOt −m/2 cos (ω0+ω)t +m/2009 (ω0−ω)1) If the captured and transmitted wave is removed using a −e balance transformer or the like, an AM output wave is obtained according to equation 2.

uM 4Io m/2 (cog(coo +fJ, l
) t--cog(ω0-ω)t) 1. ---------2 formula.

c) When comparing formulas 1 and 2 based on the above results.

Output curvature value ic obtained by superimposing and adding iFM and iAM
MP can be 3 types - e wife 1.

icMP =a iFM +iAM =a 10 [[JO5in(UOt −[(Jl (mf) +rrV2)(cos (C
LIO+0J)t)] −[(Jl (mf) +j m/2)(cos (
IjJo-oJ)t) ) J-------= 3 lengths.

There- e If value is managed constant and AM is titrated for 4 lengths at the same time with m value! ! ! If you give it.

Jl　(mf)−ψ　　　　　---4 length.

1) The lower sideband component (ω0-ω) can be used and canceled by superimposing and adding the 1-length parallel output wave and the 2-type M output wave.

2) Similarly, by subtracting the FM wave of the first equation and the AM wave of the second equation, the so-called upper sideband component (CLIO-) can be used and eliminated.

As can be seen from the above (1) the present invention utilizes the phase relationship between the FM wave and the 1W band wave that is generated to generate the upper sideband wave.

Or remove and occupy the lower 11# wave? If area rights are to be reformed and curtailed in a concise manner.

d) The present invention is highly effective when applied to an information transmission method using pulsed waves of multiple frequency values (hereinafter referred to as MPFM).

In KPFM, the modulation signal is deepened in synchronization with the output wave every n cycles, so when n w is set above, it becomes ω〇−ω, and the output current if becomes Equation 1 to Equation 5.

λf =s 10 (JO(if) 5illωQt+
w , rl (mf') CO92CL)Ot) --
--5E.

That is, as can be seen from Equation 5, there is no lower @band wave in this 14p FM output wave from the beginning, and since the sideband waves are unbalanced, AM is mixed.

On the other hand, in the same article, if the QAMAM wave is iAMa, equations 2 to 6 can be derived.

1A) ia -s -IOm/2 cos 2 (L)
Ot---6 formula.

In other words, the lower sideband wave does not exist from the beginning in this opening as well, for both waves of formulas 5 and 6.

If we perform coefficient matching to Jl (mf) x m/2 and calculate both waves by i1 weight, the sideband components will be canceled and the output wave will be 1st wave. Be patient.

iMPFM =s if +iAMa w IQ , y□ (mf) Sin■Otm IO,
T□ (mf) sin wt --------7 formula.

Equation 7 (Main iMPFM extracts from the modulated wave component, (
Indicates that there is an output wave-e that does not accompany the 51 band, and the occupied band is the smallest! ! ! It means that there is ie.

From the above, when the present invention is applied to MPFM.

At the same time, it has the minimum occupied bandwidth, and at the same time, the amplitude is 4 less when the output frequency shifts to the higher side, and increases at the lower side, which is an unconventional output wave in terms of the type of material. f
I! There is also an effect on noise characteristics.

To actually obtain the output wave of formula 7, the output m(
It is necessary to use an opportunity modulator 2 that can synchronize K and AM simultaneously, such as a modulator such as the Showa Co., Ltd. License No. 039 Axis No. 5.

K) There is a feeling that the MPFM to which the present invention is applied may have poor noise resistance because it contains A14 components, but in reality, the AM component of the present invention cancels sideband waves as described above. is not necessary for transmitting signals. In other words, control the amplitude with the receiver! ! If this component is removed using a device, it is possible to remove the normal FM dark wave, noise W component related to sideband wave reproduction and linear distortion, transmission line sudden noise, etc., without damaging the characteristics of the river wave.

In addition, if the 1-resolution is sufficient for applications, it can be used with conventional toilets such as Fusai Stasile and Trahis.

m key is possible.

The following is an example of implementing the present invention, which uses the center frequency Fc and ASCII as the transmission code, and is applied to MPFM using telephone conferences (0.3 to 3.4 KHz). .

In order to minimize the occupied bandwidth, significant frequencies are arranged in units of 1-. Since the ASCII code has 8 pits, at least according to II theory, there are 256 +A codes.
h Fc -128Hz # Fc, L H!
<AsCX code FN~ao (lb decimal) wo, Fc
+1 Hz, ~Fc +128 Hz, 2 ASCII code 7F, 00 wo I If it is made to correspond in Hz increments, only PPM of occupied band 44, 25 & decimal can be implemented. (11
8wa Button Holding Permit No. 282613, Information Transmission System-
FC must be set at 854 Hz or higher to keep mf below 0.3.

In order to realize the MPFM wave of (g) to), a Sho f KJ61 No. 039565 2 frequency modulator (hereinafter referred to as FNC) is used as a modulator.

FN (by 4 in Figure 2, the ASCII code is set as a high-order !r address, and the low-order address generated by itself is
A sine wave for one period is read out from the memory circuit to the input A, and is converted from digital to analog (DAC) to produce an output wave.

To implement the present invention, the maximum amplitude line is calculated from the input ASCII code, converted into a sine wave, and delivered to a storage circuit, which is then used as an output wave by FNC.

Jl (mf) x m/2, m m Am /
From A.O.

Am -2AOJl (mf) Dn top x Am sin (2yAa Engineering Fc/10)
Here, Dnl is the memory value, Ac1d is the lower Ir
The response value Fc / 10 is the constant for Fc when the internal clock value of FNC is 100 MHz.
(See No. 65).

The FNC output wave in this embodiment is the first (Jl).

Immediately, Te5t A B C-----t ASC engineering I-e transmission +1) li type fp>), ASCII
No Tj: D4 (16 decimal water) from fe to Fc -8
5) (z, similarly 1.teel:!65 so FC+
27) Lz, sli F3'/! From Fc −
116Hz, t jj74 power) et Fa+
A pulsed sine wave of one period with a frequency value of 127 m------ continues.

Taking advantage of the feature of the present invention that M minute (mf) changes almost linearly from mffe, 3 to 0IYFl, we create a sine wave whose Am value is the value multiplied by the input hexadecimal ASCII cheater. The value is adjusted and added so that the sideband wave is reduced by i!i.

H) As described above, according to the present invention, a unit channel with the minimum possible occupied bandwidth is created -r! Therefore, it is possible to carry out dense frequency division multiplex communication up to the function of the p-wave device for channel separation on the receiving side.

At the same time, since the minimum reception bandwidth is required, it increases in proportion to the bandwidth. This has the effect of minimizing thermal noise, transmission line distortion noise, interference noise, etc.

[Brief explanation of the drawing]

FIG. 1 shows an output waveform of an example in which the present invention is applied to an MPFM.9 In order to emphasize the features of the present invention, the beginning of the period and the pseudowidth are exaggerated compared to the actual values. Figure 2 shows one of the compound transformers used in the embodiment of the present invention.
Reprinted from No. 039565 of ``Patent of 1988'', May 1986, Director General of the Japan Patent Office, 1, Indication of Case, Patent No. 273977 of 1988. 2. Title of the invention: Information transmission system. 3. With the case of the person making the amendment! Section 71 Patent applicant. Address: Han 243-02゜4, date of amendment order (shipment date): January 26, 1986. 5. Drawings subject to correction. 6. Contents of correction Additional paper. Procedural Correction Group (Hojo) Published May 23, 1988, Shōl
63 $ May Day

Claims (1)

[Claims] A) In an information transmission system based on frequency modulation (hereinafter referred to as FM), shallow modulation with a modulation index mf of less than 0.3 is performed to generate sidebands equal to or higher than the second sideband. Manage so that it does not occur. Next, the FM output wave is negatively amplitude modulated by an appropriate modulation m (
(hereinafter referred to as AM) to cancel out and eliminate the upper sideband component. This is an information transmission method in which the occupied bandwidth is reduced by the above methods. (b) The information transmission system according to claim (a), which combines a process of appropriately controlling the frequency value of the modulated wave itself to reduce or eliminate the lower sideband component to a direct current component. C) When designing an information transmission system using the FM method, including frequency division multiplex communication, plan in advance so that the spectrum within the transmission band is averagely dispersed, and add sideband components that occur at appropriate frequency positions to AM. The information transmission system according to claim 1), which employs a configuration in which the transmission bandwidth is utilized without gaps by processing the waves by combining the weight of the waves and a filter.