• 热门标签

当前位置: 主页 > 航空资料 > 国外资料 > ICAO >

时间:2010-07-21 23:22来源:蓝天飞行翻译 作者:admin
曝光台 注意防骗 网曝天猫店富美金盛家居专营店坑蒙拐骗欺诈消费者

on-channel power rises to the equivalent of at least four times co-channel interference at which a receiver shall be capable of
the estimated noise floor for at least 0.5 milliseconds. demodulating without degradation in BER.
6.9.5.5.2.2 The value of P2 shall be 12 dB.
6.9.5.3.4 Channel busy to idle detection
6.9.5.3.4.1 A VDL Mode 4 station shall employ the
following means to determine the channel busy to idle
transition.
6.9.5.3.4.2 Measurement of transmission length. When
the training sequence has been detected, the channel busy
state shall be held for a period of time at least equal to
5 milliseconds, and subsequently allowed to transition to the
idle state based on measurement of channel power.
6.9.5.3.4.3 Measurement of channel power. When not
otherwise held in the channel busy state, a VDL Mode 4
station shall consider the channel idle with at least a 95 per
cent probability if on-channel power falls below the equivalent
of twice the estimated noise floor for at least 0.9 milliseconds.
6.9.5.6 FM BROADCAST INTERFERENCE IMMWJITY
PERFORMANCE FOR VDL MODE 4 RECEIVING SYSTEMS
6.9.5.6.1 A VDL Mode 4 station shall conform to the
requirements defined in section 6.3.5.4 when operating in the
band 11 7.975-1 37 MHz.
6.9.5.6.2 A VDL Mode 4 station shall conform to the
requirements defined below when operating in the band
108-1 17.975 MHz.
6.9.5.6.2.1 The VDL Mode 4 receiving system shall meet
the requirements specified in 6.3.5.1 in the presence of
two-signal, third-order intermodulation products caused by
VHF FM broadcast signals having levels in accordance with
the following:
2N, + N, + 72 5 0
6.9.5.4 RECENER~TRANSMITINTTEERRA CTION
for VHF FM sound broadcasting signals in the range
6.9.5.4.1 Receiver to transmitter turnaround time. A VDL 107.7-1 08.0 MHz
Mode 4 station shall be capable of beginning the transmission
of the transmitter power stabilization sequence within and
16 microseconds after terminating the receiver function.
6.9.5.4.2 Frequency change during transmission. The
phase acceleration of the canier from the start of the
synchronization sequence to the data end flag shall be less than for VHF FM sound broadcasting signals below 107.7 MHz,
$0 Hz per second:
where the fiequencies of the two VHF FM sound broadcasting
signals produce, within the receiver, a two-signal, third-order
6.9.5.4.3 Transmitter to receiver turnaround time. A VDL intermodulation product on the desired V~~ ~~d~ 4
Mode 4 station shall be capable of receiving and demodulating
with nominal performance an incoming signal within 1 ms
after completing a transmission. N, and N, are the levels (dBm) of the two VHF FM sound
broadcasting signals at the VDL Mode 4 receiver input.
Note.- Nominal performance is defined as a bit error rate Neither level shall exceed the desensitization criteria set forth
(BER) of I @ . in 6.9.5.6.2.2.
Af = 108.1 - f,, where f, is the frequency of N,, the VHF FM
6.9.5.5 PHYSICAL LAYER SYSTEM PARAMETERS
sound broadcasting signal- closer to i 08.1 MHz.
Note.- The FM intermodulation immunity requirements
6.9.5.5.1 Parameter PI (minimum transmission length) are not applied to a VDL Mode 4 channel operating below
108.1 MHz, and hence frequencies below 108.1 MHz are not
6.9.5.5.1 .I A receiver shall be capable of demodulating a intended for general assignments.
transmission of minimum length PI without degradation of
BER. 6.9.5.6.2.2 The VDL Mode 4 receiving system shall not
be desensitized in the presence of VHF FM broadcast signals
6.9.5.5.1.2 The value of PI shall be 19 200 bits. having levels in accordance with Tables 6-5 and 6-6.
2511 1104
No. 79
Annex I0 - Aeronautical Telecommunications
6.9.6 Link layer
Note.- Details on link layer firnctions are contained in the
Manual on VDL Mode 4 Technical Specifications.
6.9.7 Subnetwork layer and SNDCF
Note.- Details on subnetwork layer functions and SNDCF are
contained in the Manual on VDL Mode 4 Technical
Specifications.
6.9.8 ADS-B applications
Note.- Details on ADS-B czpplication functions are contained
in the Manual on VDL Mode 4 Technical Specifications.
2511 1104
No. 79
Annex 10 - Aeronautical Teleconununications
TABLES FOR CHAPTER 6
Table 61. Modes 2 and 3 data encoding
Table 62. Modes 2 and 3 modulation stability
Table 6-3. Scrambler functions
Function Data in Data out
VDL Mode
Mode 2
Mode 3
scrambling
descrambling
clean data scrambled data
scrambled data clean data
Aircraft Modulation
Stability
+ 0.0050 per cent
+ 0.0005 per cent
Table 6-4. Physical services system parameters
 
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址:附件10--航空电信an10_v3_1ed_amend_79(11)