DOCUMENT 810-5; REV. D DSN/FLIGHT PROJECT INTERFACE DESIGN TCI-10; REV. A DSN TELECOMMUNICATIONS INTERFACES, 64-METER ANTENNA SUBNET (insert this modular document in your 810-5; Rev. D Handbook) EFFECTIVE DATE: 1 October 1977 Change 1: 15 January 1978 ------------------------------------------------------------------------------ Approved by: B.D.L. Mulhall (signed) A. PURPOSE. This module describes the primary telecommunications parameters pertaining to the DSN 64-meter antenna station subnet. B. SCOPE. The intent of this document is to provide the significant telecommunications parameters for system noise temperature, transmitter, and other RF-related data in sufficient detail to allow the telecommunications engineer to calculate link performance. C. LOCATION OF MATERIAL. 1. Contents. -------- Designator Title Page ---------- ---------------------------------------------------- ---- D. GENERAL INFORMATION................................. 3 D.1. Deep Space Network.................................. 3 D.2. Telecommunications Parameters, S- and X-Band........ 3 Page 1 of 16 Change 1: 15 Jan 78 ------------------------------------------------------------------------------ 819-5; Rev. D TCI- 10 2. Illustrations. ------------- Figure Title Page ------ --------------------------------------------------------- ---- 1 Increase in System Noise Temperature vs Elevation Angle for 64-Meter Antennas, S- and X-Band............... 5 2 Calculated Gain Reduction at Transmitted and Received Frequencies vs Angle Off Boresight for 64-Meter Antenna Stations................................................. 15 3. Tabular Data. ------------ Table Title Page ----- --------------------------------------------------------- ---- 1 Primary Telecommunication Parameters for 64-Meter Antenna Station Subnet........................................... 6 2 Loss Due to Wind Loading, 64-Meter Antenna Station....... 16 3 X-Band Antenna Gain for 64-Meter Antenna Subnet Including Atmospheric Effects...................................... 16 Page 2 of 16 ------------------------------------------------------------------------------ 810-5; Rev. D TCI-10; Rev. A D. GENERAL INFORMATION. 1. Deep Space Network. ------------------ The DSN includes three basic subnets as follows: (a) 64-meter diameter antenna subnet (DSS 14, 43, 63) (b) 26-meter diameter antenna subnet (DSS 11, 44, 62) (c) 26-meter diameter antenna subnet (DSS 11, 42, 61) which will be upgraded to a 34-meter subnet per the schedule in Figure 1 of TCI-30 Other elements of the DSN include a Compatibility Test Area (CTA 21) at JPL, Pasadena, and a similar configuration of equipment in the Spaceflight Tracking and Data Network (STDN) station at Merritt Island, Florida. 2. Telecommunications Parameters, S- and X-Band. -------------------------------------------- The more significant telecommunications parameters for the 64-meter antenna subnet are given in Table 1. They include (1) S-band transmit characteristics for 20 and 100 kilowatts, (2) S- and X-band receive characteristics for traveling wave maser operation and Block III or Block IV receiver configurations, and (3) characteristics for frequency and timing. See TCI-40 for S- and X-band weather-induced system degradations. The operating system noise temperature (Top) varies as a function of elevation angle, and typical values for the 64-meter antenna stations are given Figure 1. Nominal reduction in 64-meter antenna gain as a function of angle off boresight is given for S-band transmission and S- and X-band reception in Figure 2. The degradation of system noise temperature as a function of Sun-Earth- probe angle is given in TCI-40. Page 3 of 16 ------------------------------------------------------------------------------ 810-5; Rev. D TCI- 10; Rev. A S-band and X-band gain reduction due to wind loading is listed in Table 2. Cumulative probability distributions of wind conditions are given in TCI-40. Variation in 64-meter antenna gain at X-band are given in Table 3. These data include atmosphere attenuation which can be calculated by formulas given in TCI-40. The variation in antenna gain at S-band is a loss of 0.4 dB at 10 degrees elevation. This loss decreases and is negligible ( 12 hours | | | | | | | Station time | 20 microseconds | Rubidium standard | | relative to DSN| | synchronized by OTS | | master clock | | | | | 3 milliseconds | Calib. by HF radio | |============================================================================| Page 13 of 16 ------------------------------------------------------------------------------ |============================================================================| | Table 1. Primary Telecommunication Parameters for 64-meter Subnet | | (Sheet 9 of 9) | |============================================================================| | Frequency and Timing | |============================================================================| | Characteristics | Value | Remarks | |-----------------+-----------------------------------+----------------------| | | | | | DSN master clock| 50 microseconds | Calibrated by | | relative to NBS| | portable cesium | | | | clock | | DSS frequency | | | | offset relative| | | | to DSN master | | | | reference | | | | frequency | | | | | | | | Rubidium or | 1 part in 10^11 | | | cesium beam | | | | standard | | | | | | | | Hydrogen maser| 2 parts in 10^13 | Projected operational| | | | by July 1978 | |============================================================================| Page 14 of 16 ------------------------------------------------------------------------------ Figure 2. Calculated Gain Reduction at Transmitted and Received Frequencies vs Angle Off Boresight for 64-Meter Antenna Stations. Page 15 of 16 ------------------------------------------------------------------------------ 810-5; Rev. D TCI- 10; Rev. A Table 2. Loss Due to Wind Loading, 64-Meter Antenna Station |===========================================| | Wind Speed | S band | X band | |-----------------+ Loss | Loss | | (Km/hr) | (mph) | (dB) | (dB) | |=========+====================+============| | 32 | 20 | Negligible | 0.05 | | 48 | 30 | Negligible | 0.3 | | 72 | 45 | 0.2 | 1.5 | |===========================================| Table 3. X-Band Antenna Gain for 64-Meter Antenna Subnet Including Atmospheric Effects (See Notes below) |=====================================================| | Elevation | DSS 14 | DSS 43 and 63 | | Angle |--------------------+--------------------+ | (degrees) | System | Gain | System | Gain | | | Efficiency | (dBi) | Efficiency | (dBi) | |===========+============+=======+============+=======| | 10 | .376 | 70.8 | .363 | 70.6 | | 15 | .390 | 70.9 | .393 | 71.0 | | 20 | .402 | 71.1 | .417 | 71.2 | | 25 | .412 | 71.2 | .437 | 71.4 | | 30 | .419 | 71.3 | .452 | 71.6 | | 35 | .423 | 71.3 | .464 | 71.7 | | 40 | .426 | 71.3 | .470 | 71.7 | | 45 | .426 | 71.3 | .471 | 71.8 | | 50 | .423 | 71.3 | .471 | 71.8 | | 55 | .418 | 71.2 | .465 | 71.7 | | 60 | .411 | 71.2 | .454 | 71.6 | | 65 | .401 | 71.1 | .439 | 71.5 | | 70 | .389 | 70.9 | .419 | 71.3 | | 75 | .375 | 70.8 | .397 | 71.0 | | 80 | .358 | 70.6 | .368 | 70.7 | |=====================================================| Notes ----- 1. See TCI-40 for procedures for estimating atmospheric effects on antenna gain. 2. Refocusing of the subreflector as antenna elevation angle changes is required to achieve these values. If refocusing is not performed, from 0. 8 to 1. 2 dB, loss in gain will occur. Page 16 of 16 ------------------------------------------------------------------------------