KR100893575B1 - Apparatus and method in ultra-wideband wireless communication system - Google Patents

Abstract

The present invention is the second relates to a wireless communication apparatus and method, a transfer K had multiple access in which modulation user of a phase binary signal data bits and then MHP pulse of the orthogonality in the M random time hopping code and N mutually Increasing the multiple access capacity of the system, including a pulse order-time hopping multiple access code generation unit for generating and allocating a two-dimensional code. According to the present invention, since MHP pulses having mutually orthogonality are used, Even if the pulse is transmitted, the collision problem between the pulses does not occur, thereby enabling the high-speed data transmission. In addition, since data is transmitted and received in the baseband, the structure of the system is simple in hardware implementation, and thus the baseband ultra wideband wireless communication system can be implemented with low power.

Ultra Wideband Radio, WPAN, Pulse Order-Time Jump Code, MHP Pulse

Description

Apparatus and method in ultra-wideband wireless communication system

1 is a block diagram of an ultra-wideband wireless communication device according to the present invention

2 is a conceptual diagram showing the operation of the transmitting apparatus according to the present invention.

3 is a conceptual diagram showing the operation of the receiving apparatus according to the present invention;

4A and 4B are block diagrams illustrating a multi-user connection method in a transmitting apparatus.

5 is a flow chart for the ultra-wideband wireless communication method according to the present invention

Explanation of symbols for the main parts of the drawings

100. Transmitter 110. Binary phase signal modulator

120. Time hopping code generator 130. MHP pulse generator

140. Pulse order-time jump multiple access code generator 150. Multiplier

160. Transmitter 200. Receiver

210. Receiver 220. Signal correlator

230. Average 240.

TECHNICAL FIELD The present invention relates to ultra-wideband wireless communication. Specifically, the present invention provides data transmission speed and reception performance by providing pulse order-time hopping multiple access using MHP (Modified Hermite Polynomial) pulses and time hopping codes. It relates to an ultra-wideband wireless communication device and method to improve the.

The transmission technology of the previous wireless communication system uses ultra-wideband (UWB) wireless communication, in particular, ultra-wideband impulse radio (UWB), compared to converting a baseband signal into a radio frequency signal using a carrier wave to transmit and receive data. -Ipulse radio (UWB-IR) -based wireless communication system transmits and receives data to baseband using short pulses of less than 1 nanosecond. Communication method.

In a multi-access environment such as WPAN, which requires high-speed data transmission, carrier-based multi-band orthogonal frequency division multiplexing (MB-OFDM) or direct sequence code division multiple access (DS-CDMA) supports excellent reception performance and data rate. The method is mainly used.

Also, in the fields requiring precise location recognition such as low power and low speed sense network or location recognition, UWB-IR based method without using carrier is spotlighted as next generation short-range wireless communication technology.

In the conventional multiple access UWB-IR technique, pulse position modulation (PPM) is defined as follows.

Where k is the number of users, p (t) is the transmission pulse, and T _f is the frame time interval.

는 k번째 사용자의 데이터를 전송하기 위해 N _s 번 반복되는 프레임 중에서 j번째 프레임의 신호의 데이터 비트 값이다.And c _j ^(k) is the j th time jump code of the k th user, T _c is the chip time interval, δ is the time shift used to distinguish data bits '0' and '1',

Is the data bit value of the signal of the j th frame among frames repeated N _s times to transmit data of the k th user.

In the conventional multiple access UWB-IR technology, pulse amplitude modulation (PAM) is defined as follows.

That is, the PPM method modulates data depending on whether the pulse is at a predetermined position and a time delayed position by δ , and time N _s pulses for one bit to obtain a desired bit error rate (BER). It is a method of repeatedly transmitting by using a hopping code, and PAM is a method of repeatedly transmitting data by modulating data according to whether a pulse value is (+) or (-) at a predetermined position.

When multiple access users transmit pulses at the same location, collisions between pulses occur and data cannot be received.

Therefore, when the number of users simultaneously accessing in a multi-access environment increases, the data rate and the BER drop sharply, and thus cannot be used in a field requiring high-speed transmission such as WPAN.

In the conventional multi-access UWB-IR technology, an M- aryx transmission method is used for high-speed data transmission. An M- ary PPM method using N time transitions and a multi-level using N pulse levels are used. ) M binary PAM method, and a combination of the two methods.

On the other hand, in the case of MB-OFDM or DS-CDMA, it has excellent reception performance and a high data rate, but it has a disadvantage in that the structure of the system is complicated because the carrier is used.

The present invention is to solve the problems of the prior art ultra-wideband wireless communication system, and provides a pulse order-time hopping multiple access using MHP (Modified Hermite Polynomial) pulses and time hopping codes having mutually orthogonality. It is an object of the present invention to provide an ultra-wideband wireless communication apparatus and method for improving the data transmission rate and the reception performance.

According to the present invention, two-dimensional pulse order is given to K users simultaneously connected using N MHP pulses and M random time hopping codes having orthogonality to each other in a baseband multiple access environment such as WPAN. By providing time-bound multiple access, it implements more efficient short-range wireless communication technology that provides excellent reception performance and data transmission rate, and does not use carrier, so the transceiver structure of the system is simple, low-power, compact, ultra-wideband wireless communication The purpose is to provide a system.

The ultra-wideband wireless communication apparatus according to the present invention for achieving the above object is a time hopping code generator for modulating the data bits of the K multi-access user to be transmitted into a binary phase signal and then generating M random time hopping codes. MHP pulse generation unit for generating MHP pulses having orthogonality between N through differential; Pulse order-time for allocating two-dimensional code to K multiple access users using the time hopping code and time-shifted MHP pulse And a multiplexing multiple access code generation unit, characterized in that to provide a two-dimensional pulse order-time hopping multiplexing.

The ultra-wideband wireless communication apparatus according to the present invention for achieving the above object is to correlate the received signal by pulse order-time hopping to detect the transmission data bits of K multiple access users in the received signal on the channel. N signal correlators for obtaining a correlation degree; An average unit for averaging by the frame unit in the calculated correlation; And a hard decision unit determining a bit value from the average unit value.

According to another aspect of the present invention, there is provided a method of ultra-wideband wireless communication, comprising: modulating data bits of K multiple access users to be transmitted into a binary phase signal; generating random M time hopping codes, and N through derivatives. Generating MHP pulses and mapping pulse order-time hopping to K multiple access users; And generating a transmission signal by multiplying the signal mapped to the binary phase signal.

In the ultra-wideband wireless communication method according to the present invention for achieving another object, in order to detect the transmission data bits of K multiple access users in the received signal on the channel, the received signal is mapped to each pulse order-time hopping signal Calculating each N correlations; averaging frame-wise at each calculated correlation; And determining each bit value from the averaged value.

Hereinafter, a preferred embodiment of the ultra-wideband wireless communication apparatus and method according to the present invention will be described in detail.

Features and advantages of the ultra-wideband wireless communication apparatus and method according to the present invention will become apparent from the detailed description of each embodiment below.

1 is a block diagram of an ultra-wideband wireless communication device according to the present invention.

The present invention is a wireless communication system that requires high-speed data transmission, such as short-range multimedia communication such as wireless personal area network (WPAN), without using a carrier (carrier), mutually orthogonal MHP pulse and time hopping code This enables the pulse order-time hopping multiple access to be implemented.

The ultra-wideband wireless communication apparatus according to the present invention modulates the data bits of the K multiple access users to be transmitted into a bi-phase signal, and then performs orthogonality between M random time hopping codes and N mutually. The MHP pulses may include a pulse order-time hopping mapping unit for allocating two-dimensional codes to K multiple access users using MHP pulses.

The ultra-wideband wireless communication device according to the present invention includes a transmitter 100 and a receiver 200 as shown in FIG.

The transmission apparatus 100 performs a binary phase signal modulator 110, a time hopping code generator 120, an MHP pulse generator 130, a mapping unit 140, a multiplier 150, and a transmitter 160. It is made to include.

In detail, when the data bits of the K users simultaneously connected are input, the transmitter 100 performs a binary phase signal modulator 110 for modulating the received bits into a binary phase signal, respectively, For randomly positioning pulses repeated N _s times for each data bit, time jump code c _j ^(m) and chip time Using the time jump code generation unit 120 to generate M time jump codes using T _c and K multiple accessors simultaneously, each time shift is used in consideration of the derivative time for each order, The MHP pulse generator 130 generates 0 order MHP pulses and then generates N MHP pulses having orthogonality through the nth derivative, and outputs the time hopping code and time-shifted MHP pulses. The mapping unit 140 multiplies the output of the binary phase signal modulator 110 with the output of the mapping unit 140 by allocating a pulse order-time hopping two-dimensional code to K users who are simultaneously mapped and connected. And a multiplier unit 150 for generating output signals of K users who are multi-connected and a transmitter (Tx) 160 for transmitting the K output signals generated by the multiplier 150 to an ultra-wideband channel. do.

The transmission signal in the case of allocating a two-dimensional code of pulse order-time hopping to K users simultaneously connected is as shown in Equation (3).

Where k is the number of users, n is the MHP pulse order, and m is the time hopping code number. That is, since the total number of users k = n ⅹ m is satisfied, it can be seen that the number of users that can be connected simultaneously is determined by the number of MHP pulses and the number of time hopping codes.

For example, if you have 16 concurrent users, you can use 1 MHP pulse and 16 time hopping codes, or 2 MHP pulses and 8 time hopping codes, and also 4 MHP pulses and 4 times. You can use the hopping code, eight MHP pulses and two time hopping codes, and finally 16 MHP pulses and one time hopping code. This may be determined in consideration of the data rate and bit error rate (BER) required by the system.

The output signal of the transmitter (Tx) 160 passes through an additive white Gaussian noise (AWGN) channel, a fading channel, a UWB channel, and the like. There is no effect between MHP pulses of different orders, and they have independent relationships.

The receiver 200 includes a receiver 210, a signal correlation unit 220, a frame averaging unit 230, and a hard decision unit 240.

Specifically, the second and receiving a signal on the broadband channel receiver (Rx) (210), in the received signal pulse order - a by correlating to the time hopping the K of reference signals (reference signal) and the frame-by-frame, at the same time it transmits K name and the signal correlation unit 220 for calculating and outputting a user of the correlation, one data bit is the next frame number, so repeatedly transmitted to the N _s pulses, the correlation of frames obtained by the signal correlation unit is also the sum of the N _s dog An average unit 230 that calculates a bit unit correlation through a dividing average, and a hard decision unit that makes a hard decision on each bit using the correlation unit of bits transmitted from the average unit 230 ( 240).

Here, the method of generating the pulse order-time-bound reference signal in the signal correlator 220 is as described in the transmitter 100. The method of obtaining the correlation is obtained by integrating the received signal with the reference signal by the frame time T _f .

The hard decision unit 240 outputs the data bits of the K multiple accessors by determining which (± 1) data bit value is transmitted using the correlation value.

In the pulse order-time hopping code, the time hopping code is used to randomly position pulses repeated N _s times for each data bit of a multiple access user.

The pulse order is used to position MHP pulses of different orders at the same chip time for each data bit of a multi-access user, and generates N MHP pulses having orthogonality with each other through differentiation.

The generated MHP pulses and the time hopping code are used to generate a two-dimensional code of pulse order-time hopping and assign them to K users simultaneously connecting to increase the multiple access capacity of the system.

In the previous time hopping multiple access method, when a multiple access user transmits pulses at the same chip time, collision between pulses occurs and the data cannot be received. However, the pulse order-time hopping two-dimensional multiple access of the present invention. The method can be used independently even when multiple access users transmit pulses at the same chip time since collisions between pulses do not occur due to orthogonality between MHP pulses.

The MHP pulses are as shown in Equation 4 below.

After generating the 0th order MHP pulse, it is preferable to generate n MHP pulses having orthogonality through the nth order derivative.

For example, if the system uses three MHP pulses, the first MHP pulse is differentiated once to generate the first MHP pulse, and the first derivative MHP pulse is differentiated once more to obtain the second MHP pulse. It is preferable to produce and use.

Hereinafter, operations of the transmitter and the receiver of the ultra-wideband wireless communication apparatus according to the present invention will be described.

2 is a conceptual diagram illustrating an operation of a transmitter according to the present invention, and FIG. 3 is a conceptual diagram illustrating an operation of a receiver according to the present invention.

4A and 4B are diagrams illustrating a method of accessing multiple users in a transmitting apparatus.

2 shows the operation of the transmitting apparatus 100 according to an embodiment of the present invention, in which data bits d ⁽¹⁾ , d ⁽²⁾ , d ⁽³⁾ , ... of K users simultaneously connected. If there are 4 users currently connected, 2 MHP pulse orders and 2 time hopping codes are used, and the repetitive transmission number ( N _s ) of pulses per bit is 3 times. Lift up. The data bits d ⁽¹⁾ , d ⁽²⁾ , d ⁽³⁾ , and d ⁽⁴⁾ of the multiple access user are transmitted to b ₁ , b ₂ , b ₃ , and b ₄ through the binary phase signal modulator 110. Is converted.

In addition, the time hopping code generation unit 120 generates two random time hopping codes for four multiple accesses, and the MHP pulse generation unit 130 generates two first and second MHP pulses through differentiation. Next, using the generated MHP pulses and the time hopping code, each independent pulse order-time hopping code is mapped to a user connected at the same time in the mapping unit 140.

The multiplier 150 multiplies the output of the binary phase signal modulator by the mapped output, respectively, and generates an output signal for four multiple accessors, and then transmits the output signal on the UWB channel using the transmitter 160.

And Figure 3 shows the operation of the receiving apparatus 200 according to an embodiment of the present invention, the signal received by the receiver 210 is a signal correlator 220 using four linear correlators four reference signals By multiplying by and integrating for the frame time, the correlation value is obtained.

The average unit 230 obtains a correlation degree in bits by averaging each frame repeatedly transmitted N _s times. Using the bit unit correlation of the average unit 230, the hard decision unit 240 determines each data bit and outputs correlation values for four users as data bits.

Figure 4a shows a multi-user connection method in the transmission apparatus of the prior art.

In the UWB-IR, which is a baseband transmission system of the prior art, when a different user is located at the same chip time, a collision between pulses occurs and data cannot be received. As shown in FIG. To use separately.

Therefore, as the number of users connected at the same time increases, the time required to transmit one data bit increases, and the number of pulse repetitive transmissions per bit also decreases, which dramatically reduces the data transmission rate and BER. It will not be available on the required system.

On the other hand, in the multi-user connection method of the present invention shown in Fig. 4b, in order to solve the collision problem between pulses occurring in Fig. 4a, MHP pulses having orthogonality to each other are applied to the time hopping code in two dimensions. By accommodating concurrent users, the data rate and BER can be improved.

Comparing FIG. 4B with FIG. 4A at the same data rate, the same time hopping code is used, but by adding four MHP pulses having orthogonality to each other, the number of concurrent users increases to 16.

Thus, increased system capacity is desirable to accommodate more users or to improve the performance of the system by increasing the number of repetitive transmissions of pulses per bit.

Hereinafter will be described a wireless communication method using an ultra-wideband wireless communication device according to an embodiment of the present invention.

5 is a flow chart for the ultra-wideband wireless communication method according to the present invention.

The ultra-wideband wireless communication method according to the present invention comprises the steps of: modulating the data bits of K multiple access users to be transmitted into a binary phase signal; Generating N time hopping codes; Generating M MHP pulses; Mapping the N time-hopped codes and M MHP pulses to K users; And multiplying the pulse-order-time-mapped pulse by the binary phase signal.

The MHP pulses using the following equation,

After generating the 0th order MHP pulses, it is preferable to generate the nth order MHP pulses having orthogonality through the nth order derivative.

Specifically, first, the data bits of the K multiplexer to be transmitted are modulated into binary phase signals through the binary phase signal modulator 110 (S600).

In addition, M random time hopping codes are generated (S611), and N MHP pulses are generated through derivatives (S612).

Subsequently, the generated pulse order-time hopping code is mapped to K multiple access users (S620).

Here, the method of generating the time hopping code and the MHP pulse and mapping to each user is as described above.

Each transmitted signal is generated by multiplying the modulated K binary phase signals by the pulse order-time hopping code mapped to the K users (S630).

Subsequently, the transmitter 160 transmits signals of multiple accessors multiplied by using the ultra-wideband channel (S640).

Such a binary phase signal modulation step, MHP pulse generation and time hopping process through the derivative, multiplication process is natural is not limited to the above order can be varied.

The signal placed on the ultra-wideband channel through such a transmission step is received through the receiver 210 of the receiver 200, and the received signal is received through the signal correlator 220 to receive received signals of K multiple accessors, respectively. Correlation between K frames is obtained in correlation with a reference signal of (S650).

Since the obtained correlation of the frame unit is repeatedly transmitted N _s times per bit, the correlation per bit is calculated by averaging each frame correlation (S660).

The correlation per bit obtained by the average unit 230 determines K bit values that are multiplexed through the hard decision unit 240 (S670).

Since the ultra-wideband wireless communication apparatus and method according to the present invention uses MHP pulses having orthogonality to each other, even if pulses of different orders are transmitted at the same time, collision between pulses does not occur, thereby enabling high-speed data transmission.

Those skilled in the art will appreciate that various changes and modifications can be made without departing from the spirit of the present invention.

Therefore, the technical scope of the present invention should not be limited to the contents described in the embodiments, but should be defined by the claims.

Such an ultra-wideband wireless communication apparatus and method according to the present invention has the following effects.

First, by using the MHP pulse of order N and the M random time hopping code having orthogonality to each other in a two-dimensional pulse-order - it can provide a time hopping multiple access to increase the capacity of a multiple access system.

Secondly, two-dimensional pulse order-time hopping multiple access enables high-speed data transmission with good performance.

Third, by supporting the ultra-wideband wireless communication in the baseband, the transceiver structure of the system is simplified to implement a low-power, compact and ultra-wideband wireless communication system.

Claims (8)

A time hopping code generator for modulating the data bits of K multiple access users to be transmitted into a binary phase signal and generating M random time hopping codes; MHP pulse generator generating a pulse having a MHP orthogonality between the N through a differential; And a pulse order-time hopping multiple access code generation unit for allocating a two-dimensional code to K multiple access users using the time hopping code and the time-shifted MHP pulse. An ultra-wideband wireless communication device characterized by providing two-dimensional pulse order-time hopping multiple access. The transmission signal according to claim 1, wherein the transmission signal in the case of assigning a code of two-dimensional pulse order-time hopping,

Wherein k is the number of users, n is the MHP pulse order, and m is the time hopping code number. The method of claim 1, wherein the MHP pulses,

As it defined, and the generated MHP pulses of a zero-th order, and then, second, characterized in that used to produce n pulses having different MHP orthogonality through the n-th order differential of a wireless communication device. To detect the transmitted data bits of K multiple access users in the received signal on the channel, N signal correlators which correlate the received signal with a pulse order-time hop to correlate with a reference signal to obtain a correlation degree; An average unit for averaging by the frame unit in the calculated correlation; And And a hard decision unit determining a bit value from the average part value. The signal correlator multiplies the received signals and the reference signals in units of frames by the pulse order-time-bound K reference signals from the received signals, and then transmits K users simultaneously transmitted through frame time ( T _f ) integration. Ultra-wideband wireless communication device, characterized in that for calculating the correlation. delete Modulating the data bits of the K multiple access users to be transmitted into a binary phase signal; Generating random M time hopping codes, generating N MHP pulses through derivatives, and mapping pulse order-time hopping to K multiple access users; And And generating a transmission signal by multiplying the signal mapped to the binary phase signal. The method of claim 6, wherein the MHP pulses,

And generating n MHP pulses having an orthogonality through the nth derivative. To detect the transmitted data bits of K multiple access users in the received signal on the channel, Calculating each of the N correlations by correlating the received signal with each pulse order-time hopping to a mapped signal; Averaging on a frame basis at each of the calculated correlations; And Determining each bit value from the averaged value.

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