KR100952973B1 - Ultra Wide Band signal communication system for providing multi-service and communication method there of - Google Patents

Abstract

An object of the present invention is to provide a UWB wireless communication system of a PPM modulation scheme that can efficiently communicate with various service channels having different transmission rates. According to the present invention, in a communication system using a PPM modulation scheme such as an ultra-wideband system, the main frame is divided into service categories according to transmission speeds, and the wider the service channel bandwidth, the larger the category frame time is allocated. Therefore, it is possible to prevent waste of time resources and deterioration of service quality in multi-services having various transmission rates.

Ultra Wide Band, Pulse Position Modulation, Home Automation, Framer, Service Category, UWB, PPM

Description

Ultra Wide Band signal communication system for providing multi-service and communication method there of}

1 is a diagram illustrating a frame structure in pulse position modulation according to the prior art.

2 is a diagram illustrating a frame structure in pulse position modulation according to an embodiment of the present invention.

3 is a frame structure diagram to which time constellation modulation is applied according to an embodiment of the present invention.

4 is a block diagram schematically illustrating a home network system according to an exemplary embodiment of the present invention.

5 is a block diagram showing the configuration of a data transmission and reception unit according to an embodiment of the present invention.

6 and 7 are block diagrams illustrating in more detail the configuration of the transmitter illustrated in FIG. 5.

8 is a block diagram illustrating in more detail the configuration of the receiver illustrated in FIG. 5.

9 is a flowchart illustrating a flow of hopping code assignment, signal point modulation, and category assignment according to an embodiment of the present invention.

The present invention relates to an ultra wide band (UWB) wireless transmission system of pulse position modulation (hereinafter referred to as PPM). More specifically, the present invention relates to a UWB multiple access system and a method for multiplexing a plurality of service channels having different transmission rates into service categories.

UWB is an ultra-wideband communication system that uses a very wide frequency band. It was first developed by the US Department of Defense in the 1960s for military purposes. The transmission speed of UWB ranges from 500Mbps to 1Gbps, and does not transmit information by changing the shape of a reference frequency waveform called a carrier, and transmits pulses, electrical signals having constant periods and waveforms such as 0 and 1. Information transfer technology. Therefore, billions of high-frequency pulses per second can penetrate solid materials such as concrete or rock, and thus, there is an advantage that it is easy to identify a victim due to an earthquake or various accidents.

However, in recent years, since other communication technologies such as CDMA have been used for long-distance high-speed communication, the practicality of telecommunication is falling. Rather, because UWB consumes less power, requires no modulation / demodulation, and has a lower energy density per frequency, it is emerging as a new technology for short-range wireless communication to replace Bluetooth or WLAN.                         

In the prior art, a pulse position modulated (PPM) signal is defined as in Equation (1).

The PPM modulated signal x (t) sets the transmission cycle of the impulse v (t) in a frame repeated at a period T _f which is much larger than the impulse self period. One frame is transmitted in every frame. For example, when the logical value 1 is to be transmitted, it is delayed by δ picosecond and the logical value 0 is transmitted without any delay. In 1993, Scholtz proposed Time Hopping Multiple Access to apply UWB to data communication. Equation 2 is a multiple access scheme proposed by Sholtz.

As can be seen from Equation 2, in this manner, a multiple access signal made up of uniformly arranged pulses is likely to be damaged by catastrophic collisions in which multiple pulses are simultaneously received. In order to avoid such catastrophic collision in multiple access, each link identified by k is assigned a differentiated pulse shift pattern {C ^k j}, which is called a hopping code, and is configured as shown in Equation 3 below. This hopping code is a periodic pseudorandom code.

The structure of the frame according to the prior art is shown in FIG.

As shown in Figure 1, the entire frame (Tf) is to be composed of (T _c1 , T _c2 , T _c3 , T _c4 ) of equal size. As shown in equation (2), a full frame (T _f) is allocated such that the T _c T _c = T _f / N in order to evenly allocate the frame to the number of users N to each user uniformly. In addition, one data value is transmitted in a PPM method whose value changes depending on the pulse position during T _c .

However, if the voice telephone service user and the video service user are assigned the same T _f and T _c , the bandwidth is the same regardless of the service. Therefore, if the video service is used as a reference, a waste of bandwidth is caused for the voice telephone user, and bandwidth is insufficient for the video service user, resulting in a deterioration in service quality and a communication inability.

In conclusion, since the multiplexing scheme proposed by the prior art is suitable for a single rate service in terms of data transmission rate, it is not suitable when the UWB scheme is applied to multiservices of various speeds such as home networks or wireless Internet.

Accordingly, an object of the present invention is to provide a UWB wireless transmission system of a PPM modulation scheme that can efficiently communicate with various service channels having different transmission rates.

More specifically, an object of the present invention is to provide a multi-service multi-access UWB system and a method for grouping and multiplexing a variety of service channels having different transmission rates, such as in a home network.

In order to achieve the above object, an ultra-wideband signal transmission system according to an aspect of the present invention, the pulse position modulator for performing pulse position modulation of the transmission data; A category framer for framing the pulse position modulated data into different category frames according to transmission rates; A pulse generator for providing a reference pulse to the framed data; And a transmitter for outputting data provided with the reference pulse as an ultra-wideband signal.

In addition, an ultra-wideband signal receiving system according to a feature of the present invention, the receiver for receiving an ultra-wideband signal; A correlation receiver for identifying a category according to signal detection and transmission rate by performing correlation between the ultra-wideband signal and a plurality of signals; A pulse position detector for detecting a pulse position in a category frame of a signal detected from the correlation receiver; And a decoder for decoding the signal from which the pulse position is detected and outputting it as data.

Here, the transmission system further includes a time signal point modulator for setting the data position based on a predetermined dimension and a basis size and providing the data to the pulse position modulator. The demodulator combines the dimensions of the signal at which the pulse position is detected, and decodes the signal to output as data.

In addition, a method of transmitting an ultra-wideband signal according to an aspect of the present invention includes the steps of: dividing a transmission signal into a first frame having a predetermined size; Dividing the first frame into second frames having a size proportional to a service transmission rate; Dividing the second frame into third frames evenly by the number of users; Allocating a data capacity for each category according to a service transmission rate to the second frame, and transmitting the pulsed signal by modulating the transmission signal to which the third frame is allocated for each user.

Here, the third frame may include a fourth frame having a predetermined basis size as many as the number of dimensions.

DETAILED DESCRIPTION Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art may easily implement the present invention. As those skilled in the art would realize, the described embodiments may be modified in various different ways, all without departing from the spirit or scope of the present invention.

In the drawings, parts irrelevant to the description are omitted in order to clearly describe the present invention. Like parts are designated by like reference numerals throughout the specification. (When a part is connected to another part, this includes not only a directly connected part but also an electrically connected part with another element in between.)

Now, an ultra-wideband wireless transmission system and method according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

First, a multi-service multi-access UWB scheme proposed in an embodiment of the present invention will be described, and a system and method for implementing the same will be described.

Basic requirements for providing home network services may include:

(1) The system must be a bidirectional link.

(2) IP or Port designation should be available.

(3) It must accommodate various multi-services.

(4) Hierarchical addressing of home and service channels should be possible.

In order to satisfy the basic requirements as described above, the present invention intends to introduce the concept of “Service Category.” The home network service in the embodiment of the present invention is a connection service, a control service, a detection service, and an application service. Include.

For example, access services include internet access, telephone network access, in-house user access, and wireless network services. Control services include printer output, lighting control, gas control, home appliance control, TV channel control, infrared remote control replacement, and the like. Detection services include gas leak detection and occupant monitoring services. Application services include digital audio / text broadcasting, digital telephony, wireless internet, messenger calls, telemedicine, one-phone, distance learning services, and the like.

In the embodiment of the present invention, these services are classified into 64Kbps or less, 64Kbps, 1Mbps or less, 1Mps, 10Mps, or 50Mps based on the frequency use band. For example, each service based on the use band may be classified as follows.

64 Kbps or less: gas control, lighting control, infrared remote control

64Kbps level: voice call

1Mbps or lower: Internet connection Internet application

1Mbps class: Internet access, Internet application

10Mbps class: high speed video, high speed internet access

50 Mbps: video conferencing, high-speed Internet access

Equation 4 shows a multiple access signal according to an embodiment of the present invention.

Here, Tf is in the range of the expression (5).

In Equation 4, the total frame size is Tf, and Tq designated according to the service rate category may be classified into 50 Mbps, 10 Mbps, 2 Mbps, 1 Mbps, 64 Kbps, and 32 Kbps. The size of Tq for each category is calculated according to the data capacity to be transmitted in one frame Tf by calculating the repetition period of the signal. In order to evenly allocate the Tq time to the number of users Nc of the category, a uniform Tc 'is allocated to the users of each category such that Tc' = Tq / Nc '. In addition, during Tc ', data is transmitted in a PPM method whose value changes according to the pulse position.

Where q ^(k) is a serial number indicating a category to which user (k) belongs,

는 프레임 시작점으로부터 그 서비스 카테고리 시작점까지의 이격 시간을 나타낸다.

Denotes the separation time from the frame start point to the service category start point.

2 illustrates a frame structure according to an embodiment of the present invention.

As described above, the entire frame T _f is each composed of different T _qj , and within the same T _qj , T _qjcn is equally sized according to the number of users, that is, T _qj > T _{qj + 1.} T _qjcn = T _{qjc (n + i)} is satisfied. However, as can be found in Figure 2, the user-specific frame on a small _q3 than T T T _{q1 q3cj} is available is smaller than T _q1cj.

Therefore, the main frame T _f is divided into service categories, and the wider the service channel bandwidth, the greater the allocation of the category frame time to accommodate various service channels in the same frame.

In addition, in the multiple access scheme according to an embodiment of the present invention, a time signal point modulation method for compressing time resources by increasing the time dimension may be applied.

In the conventional wired and wireless systems, digital modulation methods such as BPSK and QAM are used to increase the amount of data. If one mono cycle signal can be transmitted without interfering with adjacent mono cycle signals, one chip second, each category frame is in the appropriate chip size unit corresponding to the coordinate axis in order to apply the concept of the signal point modulation technique to the PPM. You can partition the data by partitioning it.

For example, assuming 4 bits as the basic length of multiple signal points, 8 bits can transmit 8 bits without transmitting 256 chips, 4 bits on the x-axis, and 4 bits on the y-axis. Therefore, if 4 bits are transmitted for 16 chips primarily on the time axis, and then 4 bits are transmitted for 16 chips, then 256 chip 1-dimensional data can be represented in 16-chip coordinate 2D.

3 is a frame structure diagram to which time constellation modulation is applied to an embodiment of the present invention.

In the present embodiment, channels k and channels k + 1 of a category having a transmission rate of 8 bits / frame are exemplified.                     

As shown in FIG. 3, if Tb, the basic size of the coordinate axis, is set to 16 chips and Tq1 is assigned to 32 chips, the signal point becomes 32/16 = two-dimensional (dimension). Therefore, T _q1c1 becomes 8bit / frame, and if the frame repetition period is 32K frame / sec, the data transfer rate is 8bit * 32K = 256kbps.

Therefore, the embodiment of the present invention using the time signal point modulation results in an improvement in the transmission speed since a large amount of data can be transmitted in less time. Detailed description of designating dimensions and basis sizes in embodiments of the present invention will be described later with reference to the accompanying drawings.

4 is a block diagram schematically illustrating a home network system according to an exemplary embodiment of the present invention.

Home network system according to an embodiment of the present invention is largely the service terminal unit 100, the xDSL terminal unit 200, the xDSL device 300, the home auto communication server 400 and the Internet equipped with a wireless network interface Router switch 500.

The service terminal unit 100 may include various application devices such as home appliances, one-phone telephones, home radios, and video interphones, and their use frequency bands and transmission speeds may be different. The xDSL terminal unit 200 includes a home automation service (HAS) channel module 210.

The HAS channel module 210 includes a UWB HAS line unit 211, a HAS framer 212, an HAS manager 213, and an Ethernet-UWB line unit 214. The connection relation and operation of the service terminal unit and the HAS channel module will be described in detail with reference to the accompanying drawings.

Data transmitted and received by the HAS channel module may be transmitted to the HAS communication server 400 or the Internet router device 500 through the subscriber device 220 such as ATU-R and the xDSL device 300.

5 is a block diagram illustrating data transmission and reception operations occurring between a service terminal unit and an XDSL terminal.

The transmitter 600 includes a signal point PPM modulator 610, a category framer 620, and a transmitter 630. The receiver 700 includes a correlation receiver 710, a PPM detector 720, and a time signal point decoder 730.

The data di input to the transmitter is subjected to time signal point modulation and PPM modulation through the time signal point PPM modulator 610, and a category frame is determined and framed by the category framer 620. The signal in the form of a frame is transmitted to the receiver 700 through a transmission medium, and the signal is detected by the correlation receiver 710. In the detected signal, a pulse position is detected by the PPM detector 720 to perform time signal point demodulation corresponding to each channel.

6 and 7 are block diagrams illustrating the configuration of the transmitter 600 in more detail.

Hereinafter, the components shown in FIGS. 6 and 7 will be described in connection with the components shown in FIG. 5.

The data to be transmitted is encoded by the signal point encoder 611 in a predetermined dimension and a basic size. The signal point coded data is PPM modulated by the PPM modulator 612. Channel hopping timing generator 613 provides proper hopping timing to prevent collisions between pulses of PPM modulated signals. As described above, the PPM modulated signal is transmitted to an appropriate category framer through the multiplexing bus to be framed. At this time, the category timing generator 621 provides timing suitable for the category frame. The framed signal is output via the transmitter 630 as a UWB signal. The pulse generator 631 provides a high frequency pulse to the transmitter 630, and the transceiver timing generator 632 provides the transmitter 630 with a timing necessary for transmission and reception.

8 is a block diagram illustrating in detail the configuration of the receiver 700 illustrated in FIG. 5.

When the UWB signal is received, signal detection is performed by the correlation receiver 710. Here, the received signal is correlated with a plurality of signals, and the signal is detected through the correlation value. The service category of the transmitted signal is easily identified through the frame size of the detected signal. The correlated receiver 710 is shifted by a predetermined period to perform signal detection.

The pulse position is then detected via the PPM detector 720. The pulse position information detected from the plurality of PPM detectors 720 is transmitted to the signal point decoder 730 of each channel through the demultiplex bus, and the signal point decoder 730 analyzes the dimension and receives the received pulse position. The information is combined according to the above dimensions and output as final data.                     

9 is a flowchart illustrating a flow of hopping code assignment, signal point modulation, and category assignment according to an embodiment of the present invention.

Steps S100, S200 and S300 are the beginning steps of the method of hopping code assignment, signal point modulation and category assignment, respectively.

Steps S100, S200, and S300 confirm the port number of the device in steps S110, S210, and S220, respectively.

In the category assignment step 300, the registration of the user port is inquired (S320), and if not registered yet, the port number and the service speed are designated (S350, S360). If the user port is registered, the service rate is queried in step S330, and a category suitable for the service rate queried in step S340 is allocated.

Step S120 checks whether a category of data of the transmitting device is allocated, and if a category is assigned, allocates a hopping code (S130). If the category is not assigned, step S300 is performed to perform category allocation.

Step S220 examines whether a category of data of the transmission device is allocated, and if a category is assigned, allocates a default size and dimension (S230 and S240). If the category is not assigned, the process moves to step S300 and the category is assigned. Perform the assignment.

The algorithm for specifying dimensions (dimensions) and basis sizes will be described in detail below.

The time signal point PPM modulator 610 shown in FIG. 5 modulates the signal according to the dimension and the basic size defined in Equation (6).                     

PPM (fx) decomposes the one-dimensional signal fx into a phi-dimensional signal, and shifts the dimension using the maximum dimension value of each dimension as the base size. Equation 6 represents service category data having a dimension of φ. If the dimension is φ, data is transmitted divided into φ symbols.

For example, 8 bits are necessary to express through the f _x PPM configured 28 = 256 points in the pulse position modulation. In order to compress such a pulse point, fx may be displayed by dividing it into two 4-bit arrays in two dimensions. The 4-bit array is implemented with 16 point pulse position modulation. Thus, a 256 point PPM can be compressed into two 16 point PPMs.

For example, f _x can be represented by Equation 7, and in order to divide it into two dimensions, the size of one array is set to x ^4, that is, 16 chips. Therefore, PPM (f _x ) can be expressed as Equation (8).

Therefore, pulses may be disposed at 0101 and 0110 in the two-dimensional frames Tb0 and Tb1, respectively.

Although the preferred embodiments of the present invention have been described in detail above, the scope of the present invention is not limited thereto, and various modifications and improvements of those skilled in the art using the basic concepts of the present invention defined in the following claims are also provided. It belongs to the scope of rights.

According to the above-described configuration, in the communication system using the PPM modulation scheme such as the UWB system, the present invention divides the main frame by service category, and allocates a larger category frame time as the bandwidth of the service channel increases, thereby making the time resource Waste can be prevented and service quality deteriorated.

Claims (10)

In the ultra-wideband signal transmission system supporting multi-service, A time signal point modulator for providing the transmission data by setting a pulse position based on a predetermined dimension and a basis; A pulse position modulator for performing pulse position modulation of the transmission data; A category framer for framing the pulse position modulated data into different category frames according to transmission rates; A pulse generator for providing a reference pulse to the framed data; And a transmitter for outputting data provided with the reference pulse as an ultra-wideband signal. delete In the ultra-wideband signal receiving system supporting multi-service, A receiver for receiving an ultra wideband signal; A correlation receiver for identifying a category according to signal detection and transmission rate by performing correlation between the ultra-wideband signal and a plurality of signals; A pulse position detector for detecting a pulse position in a category frame of the signal detected from the correlation receiver; And a decoder for combining the dimensions of the signal at which the pulse position is detected and decoding the signal to output data. delete In the ultra wideband signal transmission method supporting multi-service, Dividing the transmission signal into a first frame having a predetermined size; Dividing the first frame into second frames having a size proportional to a service transmission rate; Dividing the second frame into third frames equally by the number of users, wherein the third frame includes a fourth frame having a predetermined basis size by the number of dimensions; And allocating a data capacity for each category according to a service transmission rate to the second frame, and transmitting the pulsed signal by modulating the transmission signal to which the third frame is allocated for each user. delete The method of claim 5, The pulse position modulated transmission signal is represented by the following equation

Where s _q ^(k) (t) is the transmission signal, v (t) is the impulse signal, Tf is the first frame size, Tq is the second frame size, Tc is the size of the third frame and Tb Is the size of the fourth frame, δ is the transmission delay coefficient and φ represents the dimension number-the ultra wideband signal transmission method represented. The method of claim 7, wherein The pulse position modulation is based on the following equation

Where fx represents a one-dimensional signal, Tb is the size of a fourth frame, and φ represents the number of dimensions. In the ultra-wideband signal transmission and reception system supporting multi-service, The transmitter is A pulse position modulator for performing pulse position modulation of the transmission data; A category framer for framing the pulse position modulated data into different category frames according to transmission rates; A pulse generator for providing a reference pulse to the framed data; A transmitter for outputting data provided with the reference pulse as an ultra-wideband signal, Receiving unit, A receiver for receiving an ultra wideband signal; A correlation receiver for identifying a category according to signal detection and transmission rate by performing correlation between the ultra-wideband signal and a plurality of signals; A pulse position detector for detecting a pulse position in a category frame of the signal detected from the correlation receiver; And a decoder for combining the dimensions of the signal from which the pulse position is detected and decoding the signal to output data. The method of claim 9, And a time signal point modulator for setting the data position based on a predetermined dimension and a basis, and providing the transmitted data to the pulse position modulator. And the decoder combines the dimensions of the signal from which the pulse position is detected, and decodes the signal and outputs the data as data.

Images