Device for transmitting CDMA (Code Division Multiple Access) signal by adopting category V line

Abstract

The invention relates to a device for transmitting a CDMA (Code Division Multiple Access) signal by adopting a category V line. The device for transmitting a CDMA signal by adopting a category V line is characterized in that a near-end device and a far-end device are connected by adopting the category V line; line cores I and II of the category V line are respectively connected with a baseband transmitting port, and line cores III and VI of the category V line are respectively connected with a baseband receiving port; a transmitted baseband Ethernet digital signal is modulated into an intermediate-frequency signal with the bandwidth of 14MHz and the centre frequency of 20MHz; and a received baseband Ethernet digital signal is modulated into an intermediate-frequency signal with the bandwidth of 14MHz and the centre frequency of 40MHz. The invention can realize the safe common transmission of a common category V line of the Ethernet signal and the CDMA signal.

Description

technical field [0001] The invention relates to the technical field of wireless communication. The five-category line is applied to a CDMA system, and the technology can realize the safe co-transmission of the five-category line of the Ethernet signal and the CDMA signal. Background technique [0002] At present, the CDMA network has achieved wide coverage of signals, but due to various objective reasons in solving the deep coverage, there are still many signal blind areas, weak areas and pilot pollution areas. The existing Ethernet only uses two pairs of cores (1, 2, 3, 6) in the five-category line to receive and send Ethernet signals, and there are two pairs of cores left. The working bandwidth of the five-category line can reach 100MHz , CDMA Category 5 line distribution system down-converts CDMA wireless signals in the radio frequency band to intermediate frequency signals with center frequencies of 70MHz and 115MHz, and uses the spare two pairs of cores of Category 5 li...

AI Technical Summary

Problems solved by technology

[0002] At present, the CDMA network has achieved wide coverage of the signal, but due to various objective reasons in solving the deep coverage, there are still many signal blind areas, weak areas and pilot pollution areas.

The existing Ethernet only uses two pairs of cores (1, 2, 3, 6) in the five-category line to receive and send Ethernet signals, and there are two pairs of cores left. The working bandwidth of the five-category line can reach 100MHz , CDMA Category 5 line distribution system down-converts CDMA wireless signals in the radio frequency band to intermediate frequency signals with center frequencies of 70MHz and 115MHz, and uses the spare two pairs of cores of Category 5 lines to transmit CDMA signals and monitoring information. However, due to the existing Ethernet The network signal is transmitted by digital baseband signal, and the spectrum distribution range of the corresponding signal is very wide, up to hundreds of MHz, which seriously interferes with the CDMA intermediate frequency signal transmitted in the five-category line, which will cause the noise floor of the equipment to rise. If it is not dealt with, It will increase by more than 15-30dB, and the noise floor of the equipment, especially the uplink noise floor of the equipment, will seriously affect the receiver sensitivity of the source base station, and even cause the base station to be paralyzed and unable to work. CDMA intermediate frequency signal interference problem, CDMA five-category line distribution system will not be able to realize combined transmission of five-category lines with Ethernet signals

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