JPH0714158B2 - Home bus system - Google Patents

Description

TECHNICAL FIELD OF THE INVENTION The present invention is used in the field of AVC and home informatization, and more particularly to condominiums and interactive CATV systems.

2. Related Art FIG. 2 shows a conventional system in which the CATV center 1 is a VT.
It is equipped with a main controller such as R4 and other packages, video equipment, broadcast wave receiving equipment from a broadcast wave receiving antenna, and security equipment, and provides various functions to each home bus system via the coaxial cable 9.

At home, to receive services such as VTR and other packaged video software, broadcast wave reception, and security, CATV
It has a modem 5, and controls the home monitor 6 in a home (6 ₁ ~6m), the Sutitasu home monitor 6 via a CATV modem 5 and sent to the center 1 by the control signal.
The video signal is branched at the information outlet 3 in front of the CATV modem 5, and a high pass filter (HPF) 2 is used for FM over 75 MHz.
It passes through the TV band signal in the down direction. Then, it is displayed on the television (TV) 8 connected by the information outlet 7.
In this case, the carrier of the CATV modem often uses subbands.

Problems to be Solved by the Invention In a CATV system and a home bus system as shown in FIG. 2, there are cases where interoperability must be considered between them. In this case, the control data and information data of the CATV system are different from the control data and information data of the home bus system, and the control data and information data of the home bus system are those of the home itself, and are taken out of the home if confidentiality is taken into consideration. It is not a proper property. Also, the camera signal in the home is not sent to the CATV system either, and it is necessary to protect confidentiality like data. The present invention satisfies these necessary functions.

Means for Solving the Problems The present invention, on the home bus system side, connects a CATV modem and a home bus controller, connects a high-pass filter in parallel with the series circuit thereof, and connects the CATV between the CATV sensor and the home bus system. A function of converting high-speed data transmitted and received bidirectionally to low-speed data of the baseband signal of the home bus is provided, and a function of establishing a communication link between the home bus controller and the terminal or between the terminals by the low-speed data is provided. .

Function FM / TV band signals are sent to the home bus by the high-pass filter, CATV control data and information data signals modulated by the sub band are sent to the home bus controller by the CATV modem, and the home bus controller sends these sub band signals. Create a baseband signal based on the original, and send it to the home bus.
Subband and FM / TV band signals can be extracted.

Embodiment FIG. 1 is a diagram showing a CATV interface configuration of an embodiment of the present invention. The same elements as those in the conventional example are given the same signals, and the description thereof is partially omitted. Since the service from the CATV center is the same as the conventional example, only new functions will be explained. It has a home bus controller (HBC) 7, which has a channel management function for exchanging bus channels of the home bus system and controlling and monitoring the channels used by the bus. The service of the video signal from the CATV center 1 is mainly a downlink service for each home, and the high-pass filter (HPF) 2 prevents the control data and information data inside the house from being sent out of the house. There is. In this case, the security controller 6 in the home is the home bus 10 in the home.
It is connected to the. The CATV modem 5 is a unit for performing communication control such as address polling from the center, and its transmission rate is a signal modulated into PSK and FSK at 48 to 64 kbps. On the other hand, in the frequency arrangement of the home bus system 10, as shown in FIG. 1, in order to keep the control data confidential at the baseband of 9.6 kbps, it is necessary to prevent the control data inside the house from going out.

For this reason, the high-pass filter 2 has a filter characteristic that allows signals in the FM / TV band to pass through.

Sub-band 12MHZ to 75MHZ is for multiple channels used in the house
Voice. It is composed of video and data, and it is considered more than free to use.

The information outlet 3 is bidirectional between the center and the CATV modem, and the directivity to the high pass filter 2 is effective in the down direction.

The information outlet 11 has a characteristic of reducing the transmission loss in the downward direction with respect to the frequency of 76 MHz or higher of the home bus 10 at the output side of the high pass filter, and the transmission loss is such that bidirectional communication or information transmission can be performed from 0 to 75 MHz. Have small characteristics. The home monitor (which may have a security controller function) 13 is connected to the home bus 10 through the information outlet 12, and has an advantage that it can be arranged in a distributed manner as compared with the system configuration of FIG. An information outlet 11 is arranged between the home buses, and the transmission loss at the entrance and exit of the home bus is small, and the branch loss is smaller than that of the conventional CATV.

As described above, the present invention relates to interoperability between a CATV system and a home bus system,
In the conventional system, a plurality of applications are connected in a star pattern from the CATV modem, but in contrast to this, the present invention can connect to the home bus system via information outlets in a decentralized manner and on the bus, increasing or decreasing the number of systems and services. ,
It is easy to change, and the control data of the home bus system and the transmission of various kinds of subband multimedia to the outside of the house can be blocked by a filter. The present invention also allows CA by inserting a simple filter into the system.
It is possible to receive the broadcast wave reception image of the TV system between the home bus systems, and to freely receive and transmit signals sent from the CATV center to the home within the home bus system.

[Brief description of drawings]

FIG. 1 is a block diagram of a home bus system according to an embodiment of the present invention, and FIG. 2 is a block diagram of a conventional home bus system. 1 …… CATV center, 2 …… High-pass filter, 3,11 ……
Information outlet, 5 ... CATV modem, 7 ... home bus controller, 10 ... home bus, 13 ... home monitor.

Claims (1)

[Claims] 1. A CATV system arranged at home comprises a CATV modem serially connected to a first information outlet, a home bus controller, a home monitor connected to the home bus controller via the home bus, and the home bus. It comprises a second information outlet connected to the above and a high-pass filter connected between the second information outlet and the first information outlet, and the first information outlet is bidirectionally connected to a CATV center. The CATV modem has a function of converting high-speed data bidirectionally transmitted / received between the CATV center and a home bus system into low-speed data of a baseband signal of the home bus in terms of speed, protocol, format, etc. The bus controller uses the low-speed data, which is control data, to connect between the home bus controller and the home monitor. It has a function of establishing a communication link between home monitors and a function of managing a subband channel of the home bus controller, and the high-pass filter has a characteristic of passing a signal having a higher frequency than the baseband and subband signals, The first information outlet has a characteristic that the directivity to the high-pass filter is effective in the downstream direction, and the second information outlet has a characteristic in the downstream direction with respect to the frequency passed by the high-pass filter at the output side of the high-pass filter. The transmission loss is reduced and the transmission loss is reduced so that bidirectional communication or information transmission can be performed with respect to the frequencies of the baseband and subband signals. Protects low-speed data and sub-band signals from being transmitted to the outside and keeps confidentiality. A characteristic home bus system.