Residual frequency offset estimation method and device suitable for testing instrument
A technology of residual frequency offset and tester, applied in the field of channel estimation
Active Publication Date: 2017-05-31
深圳市极致汇仪科技有限公司
View PDF5 Cites 5 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
For a tester with multiple RF receiving link analysis, one tester can complete the MIMO test, such as figure 2 As shown, this test method is called True MIMO test in the industry, from figure 2 It can be seen from the figure that to complete the True MIMO test, the hardware cost of 4 sets of radio frequency to baseband links is required
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment Construction
[0037] The preferred embodiments of the present invention will be further described in detail below in conjunction with the accompanying drawings.
[0038] This example first explains some terms: DUT is the device under test; EVM is error vector magnitude; MIMO is multiple input multiple output; OFDM is orthogonal frequency division multiplexing; CFO is carrier frequency difference; Composite MIMO is composite MIMO.
[0039] This example is applicable to composite MIMO system (Composite MIMO), which can effectively realize True MIMO test, frame format of IEEE802.11n and 802.11ac, such as Figure 4 and Figure 5 as shown, Figure 4 and Figure 5 The middle L-STF is 10 repeated traditional short training sequences, and the L-LTF is 2 repeated traditional long training sequences. Usually the traditional short training sequence (L-STF) is used to initially estimate the frequency offset, which is called coarse frequency offset estimation F coarse , in this example, the coarse f...
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
Login to View More Abstract
The invention provides a residual frequency offset estimation method and device suitable for a testing instrument. The residual frequency offset estimation method includes the following steps that, 1, symbolic data of a first short training sequence is intercepted to obtain a first frequency offset value, symbolic data of a first long training sequence is intercepted, the first frequency offset value is used for compensating the symbolic data of the first long training sequence to obtain a second frequency offset value, and summation is conducted to obtain a residual frequency offset value; 2, according to the residual frequency offset value, frequency offset compensation is conducted on received data symbols after first long training sequence; 3, MIMO channel estimation is conducted by means of a second long training sequence; 4, the average phase deviation of pilot subcarriers of symbols at a specific position is calculated to obtain the residual frequency offset value, and until all the specific symbols are completed, quitting is conducted. According to the method and the device, the residual frequency offset estimation is not needed to be conducted on each piece of signal data, the estimation deviation caused by noises when the residual frequency offset value is small is avoided, and the accuracy is increasingly high.
Description
technical field [0001] The present invention relates to a channel estimation method, in particular to a residual frequency offset estimation method suitable for a tester, and to a channel estimation device using the residual frequency offset estimation method suitable for a tester. Background technique [0002] In modern wireless communication systems, the combination of OFDM (Orthogonal Frequency Division Multiplexing) technology and MIMO (Composite MIMO) technology greatly improves the system capacity. The 4G mobile communication standard LTE promoted by the 3GPP organization, and the IEEE802.11n and IEEE802.11ac standards promoted by the WiFi Alliance, both adopt these two technologies. [0003] For DUTs (device under test or DUT) that support MIMO, multiple cables are traditionally used to connect multiple RF ports of the comprehensive tester to test the signal quality of multiple RF transmitting antenna ports of the DUT. For a tester with multiple RF receiving link ana...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More Patent Type & Authority Applications(China)
IPC IPC(8): H04B7/0413H04L25/02H04L27/00H04L27/26
CPCH04B7/0413H04L25/0202H04L27/0014H04L27/2657H04L2027/0026
Inventor 吴帅刘海溶吴建兵乔瑞军
Owner 深圳市极致汇仪科技有限公司