WO2018010190A1

WO2018010190A1 - Superimposing transmission method for implementing broadcast communication service by means of non-orthogonal multiple access

Info

Publication number: WO2018010190A1
Application number: PCT/CN2016/090447
Authority: WO
Inventors: 曾捷; 粟欣
Original assignee: 清华大学
Priority date: 2016-07-11
Filing date: 2016-07-19
Publication date: 2018-01-18
Also published as: CN106131945A

Abstract

The present invention relates to the field of wireless communications and provides a superimposing transmission method for implementing a broadcast communication service by means of non-orthogonal multiple access. The method comprises: first optimizing transmit power of broadcast data and communication data by means of a full search power distribution method, and determining a power distribution factor; superimposing the broadcast data and the communication data on a same time-frequency resource to obtain mixed data and sending the mixed data by means of a non-orthogonal multiple access technology; after a user receives the mixed data, detecting the broadcast data and the communication data and distinguishing the broadcast data from the communication data by means of a successive interference cancelation technology. The method can provide higher spectral efficiency and improve the capability of the system for users to access and the system throughput.

Description

Superimposed transmission method for realizing broadcast communication service by non-orthogonal multiple access

Cross-reference to related applications

The present application claims priority from the Chinese Patent Application No. "201610539998.1" filed on July 11, 2016 by Tsinghua University, entitled "A Method of Superimposed Transmission of Broadcast Communication Services by Non-Orthogonal Multiple Access".

Technical field

The invention belongs to the field of wireless communications, and in particular relates to a superposition transmission method for implementing a broadcast communication service by non-orthogonal multiple access.

Background technique

After entering 2015, global information technology continues to develop rapidly, and all walks of life are affected by the booming development of mobile Internet. Whether it is high-tech industry or traditional workers, agriculture, fishery and animal husbandry, they are faced with their own initiative to embrace information or passively accept information. Choose. The Broadband Wireless Access System (BWA) system is designed to meet the needs of a wide range of industry characteristics such as wireless coverage, connection number and connection rate guarantee, voice/video service quality requirements, and priority guarantee in complex environments. In a licensed or unlicensed frequency band of the industry, generally a wireless communication network deployed in a targeted design with a transmission bandwidth of less than 4 MHz at a lower center frequency. Its demand greatly exceeds the scope of communication and the Internet. It is not limited to the functional departments of the armed police, public security, fire control, etc., but it has penetrated into the industries related to daily life such as civil aviation, mining, shipping, logistics, catering, etc. There is an urgent need for a dedicated broadband wireless access system that meets the individual needs of the industry.

However, until 2015, the domestic 4G network operation for more than a year, the existing wireless network construction is far from the level of customization according to the individual needs of industry users, many industries still do not establish a dedicated communication network or virtual private network. The specific plan may passively choose to use public network resources to access, and there are inherent defects in controllable, security and pertinence; some industries have obtained state-approved licensed wireless due to their particularity and criticality. Communication frequency band, but still in the initial stage of the transformation of analog communication to digital communication, narrow-band communication products occupying most markets, and inter-departmental inter-connections still have a lot of obstacles; some industries have taken a lot of attempts in dedicated communication systems, respectively Purchasing equipment networking applications in accordance with European and American national standards has also taken a step in the exploration of core intellectual property rights and standardization. However, due to the gap between the industry's engineering personnel's understanding of wireless communication technology and the world's leading level, it is difficult to essentially Solve wireless communication coverage/spectral efficiency improvement and flexible and efficient networking question.

With the public network broadband mobile communication technology entered the era of 5G research, new concepts and technologies of the physical layer and the network layer emerge one after another. For many new applications and various typical application scenarios, many international leading communication companies and research machines It has proposed a newly defined air interface and a newly defined network architecture, which has presented a hundred schools of thought in the innovation breakthrough of wireless technology. A dedicated broadband wireless access system that focuses on regional and industry applications can draw on advanced wireless communication technology concepts and methods, apply cutting-edge new technology solutions as quickly as possible with new technology test platforms, and deliver advanced experience at a faster rate. Brought to professional users.

At present, broadcast data and communication data are transmitted through orthogonal multiple access, that is, broadcast data and communication data occupy different time-frequency resources, and the receiving end can distinguish broadcast data and communication data by different frequencies and different time slots. Although the prior art can also realize the transmission of the broadcast communication service, the transmission of the broadcast communication service by orthogonal multiple access limits the number of accesses of the user, which results in low spectrum efficiency and low system throughput.

Non-Orthogonal Multiple Access (NOMA) technology superimposes different signals on the same time-frequency resource, so the receiving end cannot distinguish between broadcast data and communication data by frequency and time slot, and the receiving end needs The received mixed data is demodulated using a corresponding demodulation technique such as Continuous Interference Cancellation (SIC).

The continuous interference cancellation technique first demodulates the data with higher power when demodulating the mixed data, and then eliminates the demodulated data in the original mixed data to reduce the interference on the remaining undemodulated data. Then continue to SIC demodulate the remaining data until all the data is demodulated.

Summary of the invention

The object of the present invention is to overcome the deficiencies of the prior art and propose a superposition transmission method for implementing a broadcast communication service by non-orthogonal multiple access. The invention can provide higher spectral efficiency and improve system access user capability and system throughput.

The present invention provides a method for superimposing a broadcast communication service by using a non-orthogonal multiple address, which is characterized in that it comprises the following steps:

(1) The power controller of the base station optimizes the transmission power of the broadcast data and the communication data, and the optimization method adopts a full search power allocation method, and determines a power allocation factor;

(2) The broadcast data and the communication data are superimposed on the same time-frequency resource by non-orthogonal multiple access technology to obtain mixed data and transmitted; the transmission power of the broadcast data and the communication data is determined by the power allocation factor determined in step (1). ;

(3) After receiving the mixed data sent in step (2), the user detects and distinguishes the broadcast data and the communication data by the continuous interference cancellation technology; the user first demodulates the broadcast data or the communication data with larger power in the mixed data, and then uses The continuous interference cancellation technology removes the demodulated data in the original data, and finally demodulates the remaining undemodulated data to obtain broadcast data or communication data with less power until all the data is demodulated. .

The features and benefits of the present invention are:

1 NOMA superimposes different data sent by the base station on the same time-frequency domain resources, which can provide higher spectrum efficiency and improve system access user capability and system throughput, and adopt advanced receiver algorithm for demodulation in the terminal.

2 NOMA can tend to multi-user capacity limits in both the upstream and downstream directions. Based on the NOMA technology, multiple base station data can be superimposed and transmitted in the time-frequency domain, and the SIC receiver can be used to perform iterative demodulation by using the characteristics of the multi-user channel, thereby restoring the transmitted data at the receiving end, and the transmitted data can be different. The communication data of the user may also be a mixed data composed of broadcast data and communication data.

DRAWINGS

1 is a flow chart of a superposition transmission method for implementing a broadcast communication service by non-orthogonal multiple access according to the present invention.

detailed description

The present invention provides a method for superimposing and transmitting broadcast communication services by non-orthogonal multiple access, which is further described in detail below with reference to the accompanying drawings and specific embodiments.

The invention provides a superposition transmission method for implementing a broadcast communication service by non-orthogonal multiple access, and the flow block diagram is as shown in FIG. 1 , and the specific steps are as follows:

(1) The power controller of the base station optimizes the transmission power of the broadcast data and the communication data, and the present invention uses the full search power allocation method to determine the power allocation factor; the method of the present invention uses a full search power allocation method, the allocation method is given an initial The value of the power allocation factor is then adjusted according to the step size until an optimal power allocation factor is obtained that enables the best transmission of the two types of data.

In an embodiment of the present invention, the initial power allocation factor of the broadcast data is 0.1, that is, the power of the base station transmitting the broadcast data is 0.1 of the total power, and the initial power allocation factor of the communication data is 0.9, that is, the power of the base station transmitting the communication data is occupied. The total power is 0.9; the power distribution factor is adjusted according to the step size, so that the step size is 0.05, that is, the power distribution factor of the broadcast data is increased by 0.05 for each adjustment, and the power distribution factor of the communication data is decreased by 0.05 until the two data can be obtained. The best power allocation factor that is best transmitted.

Optimized power allocation can increase system throughput, and different power allocation results may result in different system throughput and even affect user fairness.

(2) The broadcast data and the communication data are superimposed on the same time-frequency resource by the NOMA technology to obtain the mixed data and transmitted; in the non-orthogonal multiple-address broadcast communication system, the cooperatively transmitted broadcast data and the communication data are at the same frequency. The domains are directly added in the same time domain; the transmission power of the broadcast data and the communication data is determined by the power allocation factor determined in step (1).

(3) after receiving the mixed data sent in step (2), the user detects and distinguishes the broadcast data and the communication data by the continuous interference cancellation SIC technology; the user first demodulates the broadcast data or the communication data with higher power in the mixed data, After using the SIC technology, the demodulated data is eliminated in the original data, and finally the remaining undemodulated data is demodulated to obtain less powerful broadcast data or communication data until all the data is demodulated. .

Claims

An overlay transmission method for implementing a broadcast communication service by using a non-orthogonal multiple address, the method specifically includes the following steps:

(1) The power controller of the base station optimizes the transmission power of the broadcast data and the communication data, and the optimization method adopts a full search power allocation method, and determines a power allocation factor;

(2) The broadcast data and the communication data are superimposed on the same time-frequency resource by non-orthogonal multiple access technology to obtain mixed data and transmitted; the transmission power of the broadcast data and the communication data is determined by the power allocation factor determined in step (1). ;

(3) After receiving the mixed data sent in step (2), the user detects and distinguishes the broadcast data and the communication data by the continuous interference cancellation technology; the user first demodulates the broadcast data or the communication data with larger power in the mixed data, and then uses The continuous interference cancellation technology removes the demodulated data in the original data, and finally demodulates the remaining undemodulated data to obtain broadcast data or communication data with less power until all the data is demodulated. .