Satellite Characteristics | Parameter Value(s) | Notes |
---|---|---|

General: |
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Satellite Manufacturer | Alcatel Space Industries | |

Launch Date | 12/04/99 | |

Launch | Proton | |

Projected Lifetime | >12 years | |

Orbital Position | 36º E ± 0.1 º | |

Frequency Plan: |
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Operational Transponders | 12 | 31 channels, including all payloads. |

Total Transponders | 12 | The W4 satellite has a total of 31 transponders. Nineteen channels are used by the Russian payload, which is independent of the African payload. The Russian payload is described in a Satellite Data Sheet below. |

Frequency Accuracy | ±1 x 10 -6 | At satellite delivery. |

Frequency Stability |
±5 x 10 -7 ±1 x 10 -6 ±5 x 10 -6 |
Over any 24 hour period. Over any month. Over the min. operational lifetime. |

Coverages: |
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Nominal Transponder Power | 57 W Wide Beam and Steerable Spot Beam | Both coverages. |

Polarisation | Single Linear | All coverages. |

Polarisation Discrimination | 30 dB | All coverages, receive and transmit. The exact value is dependent upon the location within the coverage zone. |

Transponder Gain: |
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Fixed Gain Mode: | Precise operational gain adjustments are made according to the traffic configuration of the transponder. | |

Gain Adjustment Range | 15 dB | |

Gain Step Size | 1 dB | |

IPFD for Saturation | -(92 + X) to -(77 + X) | In dBWm-2. The value X is the G/T in dBK -1 in the direction of the location considered. |

IBO Adjustment Range | 0 - 10 dB | For a reduced Input Power Flux Density (IPFD) range of -(84 + X) to -(92 + X) dBWm -2 . |

IBO Adjustment Step Size | 1 dB | |

Automatic Level Control Mode: | ||

Dynamic Range | 15 dB | |

IPFD for Saturation | -(92 + X) to -(77 + X) | In dBWm-2. The value X is the G/T in dBK -1 in the direction of the location considered. |

IBO Adjustment Range | 0 -7 dB | |

IBO Adjustment Step Size | 1 dB | |

Beacon: |
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Number | 1 | Telemetry and ranging carrier. |

Beacon Frequency | 11 706.850 MHz |
Nominally active beacon frequency. Selectable by ground command. |

Frequency Stability | < ±50 kHz | With respect to the nominal frequency. |

Minimum EIRP | 9 dBW | Anywhere within the African coverage and within any geographical area served by the Steerable Spot Beam. |

Polarisation | Horizontal |

Satellite Characteristics | Parameter Value(s) | Notes |
---|---|---|

General: |
||

Satellite Manufacturer | Alcatel Space Industries | |

Launch Date | 12/04/99 | |

Launch | Proton | |

Projected Lifetime | >12 years | |

Orbital Position | 36º E ± 0.1 º | |

Frequency Plan: |
||

Operational Transponders | 19 | 31 channels, including all payloads. |

Total Transponders | 19 | The W4 satellite has a total of 31 transponders. Twelve channels are used by the African payload load, which is independent of the Russian payload. |

Frequency Accuracy | ±1 x 10 -6 | At satellite delivery. |

Frequency Stability |
±5 x 10 -7 ±1 x 10 -6 ±5 x 10 -6 |
Over any 24 hour period. Over any month. Over the min. operational lifetime. |

Coverages: |
||

Nominal Transponder Power | 85 W | |

Polarisation | Dual Circular | |

Polarisation Discrimination | 27 dB | Receive and transmit. The exact value is dependent upon the location within the coverage zone. |

Transponder Gain: |
||

Fixed Gain Mode: | Precise operational gain adjustments are made according to the traffic configuration of the transponder. | |

Gain Adjustment Range | 15 dB | |

Gain Step Size | 1 dB | |

IPFD for Saturation | -(92 + X) to -(77 + X) | In dBWm-2. The value X is the G/T in dBK -1 in the direction of the location considered. |

IBO Adjustment Range | 0 - 10 dB | For a reduced Input Power Flux Density (IPFD) range of -(84 + X) to -(92 + X) dBWm -2 . |

IBO Adjustment Step Size | 1 dB | |

Automatic Level Control Mode: | ||

Dynamic Range | 15 dB | |

IPFD for Saturation | -(92 + X) to -(77 + X) | In dBWm-2. The value X is the G/T in dBK -1 in the direction of the location considered. |

IBO Adjustment Range | 0 -7 dB | |

IBO Adjustment Step Size | 1 dB | |

Beacon: |
||

Number | 1 | Telemetry and ranging carrier. |

Beacon Frequency | 11 706.850 MHz |
Nominally active beacon frequency. Selectable by ground command. |

Frequency Stability | < ±50 kHz | With respect to the nominal frequency. |

Minimum EIRP | 9 dBW | Anywhere within the African coverage and within any geographical area served by the Steerable Spot Beam. |

Polarisation | Horizontal |