FS31H-4X-USR User Manual UHF Headend Repeater Unit
UHF Headend Repeater Unit User Manual Ver.
UHF Headend Repeater Unit User Manual Ver. A Version A Information in this document is subject to change without notice. All rights reserved. Please send comments to: E-mail: infotech@Fiber-Span.
UHF Headend Repeater Unit User Manual Ver. A Table of Contents 1.0 Company Info .......................................................................................................... 5 2.0 Product Intro............................................................................................................ 6 2.1 HRU Description..................................................................................................................6 2.2 Theory of Operation (Gain and Power Output)............
UHF Headend Repeater Unit User Manual Ver. A 1.0 Company Info Fiber-Span is a premier provider of advanced RF ON FIBER ® technologies and solutions for fiber optic based transmission of high fidelity radio-frequency wireless voice, data and multiservice networking applications.
UHF Headend Repeater Unit User Manual Ver. A 2.0 Product Introduction This manual covers the Headend Repeater Unit (HRU). Most applications for simple coverage enhancement solutions would require a Bi-Directional Amplifier (BDA). The HRU is FiberSpan’s equivalent technology to the BDA. The HRU has additional hardware that allows a direct connection to fiber-optic transceivers. 2.
UHF Headend Repeater Unit User Manual Ver. A The HRU amplifies RF frequencies in both the downlink and uplink paths with duplexers that provide both downlink and uplink frequency bands on a single distributed antenna system. The HRU is used to provide cost efficient wireless coverage in areas that have poor coverage. Fiber-span has additional unique hardware in the HRU that allows it to feed fiber-optic transceivers (FTU). This is the main difference between the HRU and a typical BDA.
UHF Headend Repeater Unit User Manual Ver. A When multiple RF carriers are input to an RF amplifier, the RF output power will be the input power plus the gain. Power output = Power input + Gain (in decibels) Power output = Power input x Gain (in Watts) As seen by the preceding figure, the output power tracks the input power linearly. Eventually as the input power increases, the amplifier output power reaches the output power limit.
UHF Headend Repeater Unit User Manual Ver. A A single band of RF channels is amplified in both directions (downlink and uplink). The RF channels are then distributed over a single distributed antenna system on floors where coverage is needed using coaxial cable, RF splitters and indoor ceiling mount antennas.
UHF Headend Repeater Unit User Manual Ver. A The HRU can provide coverage for multiple wireless services as shown in the following diagram.
UHF Headend Repeater Unit User Manual Ver. A The BSU (Base Station Interface Unit) combines the frequency bands of the wireless services onto a single common coaxial output. The BSU also provides adequate isolation between the frequency bands to prevent the possibility of oscillation between two or more HRU’s. A separate HRU is required for each wireless service because each HRU is capable of amplifying a single spectrum of channels.
UHF Headend Repeater Unit User Manual Ver. A 3.0 Detailed Description This section deals with the actual components that are assembled to make up the HRU. The main subassemblies are: 1. RF Amplifiers – These provide RF signal amplification. 2. Duplexers – These units separate and combine downlink and uplink spectrums and reduce interference. 3. Alarm Motherboard – This assembly combines alarms and provides a single contact closure summary alarm. 4.
UHF Headend Repeater Unit User Manual Ver. A The potentiometers are located inside the HRU cabinet are as shown in the picture below. Note: Variable Attenuators are not included with Rack-Mount versions of the HRU. When the dial indicators on each of the potentiometers are pointed towards the letter “F”, the attenuation is 0dB and the amplifier is at maximum gain. When the potentiometers are rotated counterclockwise, the gain is reduced by 2dB with every click or incremental change in position.
UHF Headend Repeater Unit User Manual Ver. A Dial Indicator Attenuation 0 1 2 3 4 5 6 7 8 9 A B C D E F 30 dB 28 dB 26 dB 24 dB 22 dB 20 dB 18 dB 16 dB 14 dB 12 dB 10 dB 8 dB 6 dB 4 dB 2 dB 0 dB For example to provide 20dB or attenuation, one of the potentiometers would be turned towards the ‘5’ position. Alternatively, both potentiometers can be positioned at the ‘A’ position to provide 10dB of attenuation each for a total of 20dB. 3.
UHF Headend Repeater Unit User Manual Ver. A and uplink frequencies are 3 MHz, 5 MHz, 9 MHz, or 10 MHz apart. Fiber-span offers the following UHF frequency arrangements. These frequency bands are listed below. UHF HRU Frequency Arrangements Passband Tx-Rx Separation 0.5 MHz 5 MHz, 9 MHz, 10 MHz 1.2 MHz 3 MHz 3 MHz 5 MHz, 9 MHz, 10 MHz 5 MHz 9 MHz, 10 MHz The UHF Downlink frequency is 457 - 462 MHz and the Uplink frequency is 464 - 469 MHz. 3.
UHF Headend Repeater Unit User Manual Ver. A A summary of these alarms is connected to an 8-pin male Switchcraft connect on the bottom of the HRU. The pin out of the male Switchcraft connector is shown in the following diagram.
UHF Headend Repeater Unit User Manual Ver. A When there is an alarm condition, there is a short circuit between pins 1 and 2. This is a summary alarm for any alarm in the HRU. 3.4 Power Supply The power utilized in the HRU is capable of supplying 150W at 28V DC. The power amplifier draws approx. 90W at 28V DC. This is to ensure that there is additional headroom for other minor active components like LNA’s and the Alarm Motherboard. 3.
UHF Headend Repeater Unit User Manual Ver. A UHF HRU Frequency Arrangements and Enclosure Sizes Passband Tx-Rx Separation Enclosure Size 0.5 MHz 5 MHz 20”x20”x9” 1.2 MHz 3 MHz 24”x24”x9” 3 MHz 5 MHz 24”x24”x9” 3 MHz 9 MHz or 10 MHz 20”x20”x9” 5 MHz 9 MHz or 10 MHz 20”x20”x9” The following table provides the power per RF channel. At these carrier levels, the RF amplifier is operating in the linear range.
UHF Headend Repeater Unit User Manual Ver. A 4.0 Setup Procedure 4.1 Cautionary Notes Before the unit can be connected to the DAS and powered on, the following cautionary notes must be observed. Before powering the unit on, it is imperative to measure the downlink composite power level at the antenna port. If the downlink signal level is excessive (>-24dBm), additional external attenuation will be required at the antenna port.
UHF Headend Repeater Unit User Manual Ver.
UHF Headend Repeater Unit User Manual Ver. A The factory set output power is 36dBm. The gain of the amplifier is defined as follows: Gain = 36dBm – Input Level Gain is also defined as follows: Gain = 80dB – Att1 – Att2 Putting the two equations together: 36dBm – Input Level = 80dB – Att1 – Att2 Att1+Att2 = 44 + Input Level The attenuators can be set simply knowing what the input power level is into the HRU downlink port. For e.g.
UHF Headend Repeater Unit User Manual Ver. A 3) Set the final output level of the HRU while connected to the antenna port. To obtain a higher output level, the attenuators can be carefully adjusted one click at a time carefully taking note of the composite output power. 4.4 Uplink Setup Generally in most applications, the uplink gain is set equal to the downlink gain. In most noncommercial UHF applications, the coverage enhancement system is downlink limited.
UHF Headend Repeater Unit User Manual Ver. A 4) Continue to increase the input signal level with the signal generator until the output signal level does not increase. This is the current setting of the ALC. 5) To change the ALC setting, turn the potentiometer on the control board as shown below for the appropriate power amplifier. 6) The ALC setting is 31-41dBm at the DAS port or antenna port. 4.
UHF Headend Repeater Unit User Manual Ver. A 6) The alarm threshold has a range of 11-41dBm at the DAS or Antenna port.
UHF Headend Repeater Unit User Manual Ver. A 5.0 Installation Procedures Fiber-Span’s HRU is made to operate in a controlled environment such as a telecom room. It is recommended that the temperature inside the room does not exceed +50°C and be above -5°C. The humidity must be 10% to 95%. 5.1 Connectorization The HRU is supplied with N-female connectors on all RF ports. It is highly recommended that 3 ft jumper cables be used to connect the HRU to coaxial cable, otherwise the RF ports will strip.
UHF Headend Repeater Unit User Manual Ver. A Surge protection is highly recommended for the coaxial feed to the external donor antenna to prevent damage to the unit during a direct lightning strike. 5.3 Adequate Anchors required Bolts of adequate strength are required to mount the HRU which weights approx. 100lbs for the standard 20”x20”x9” configuration and 150lbs for the 24”x24”x9”. A total of four (4) bolts are needed to mount the HRU.
UHF Headend Repeater Unit User Manual Ver. A 6.0 Troubleshooting In order to trouble shoot the HRU, the alarm lights must be observed as shown in the alarms section. Based on the LED’s, if corrective action does not bring the unit into normal operation by reducing gain or reducing the input signal level, the unit is most like faulty.
UHF Headend Repeater Unit User Manual Ver. A A 20dB (10W) attenuator is needed to ensure the RF output does not damage the spectrum analyzer. Most analyzers can accept a 20dBm composite RF input signal level. However, FiberSpan recommends verifying the specifications of your analyzer prior to connecting to the Power Amplifier. Set the signal generator and spectrum analyzer to the center frequency of the downlink/uplink frequency spectrum. Set the RF output level of the signal generator to -40dBm.
UHF Headend Repeater Unit User Manual Ver. A 7.0 Warranty Information The HRU carries a standard warranty period of one (1) year unless otherwise indicated on the shipping package as noted in the purchase order agreement. 7.1 Warranty Limitations The warranty is limited to the repair or replacement of the defective product. Fiber-Span will decide which remedy to provide for defective components at its own discretion.
UHF Headend Repeater Unit User Manual Ver. A Appendix A FCC requirements To comply with FCC RF exposure compliance requirements, the following antenna installation and device operating configurations must be satisfied: A separation distance of at least 1 meter distance must be maintained between the antenna of this device and all persons. RF exposure compliance may need to be addressed at the time of licensing, as required by the responsible FCC Bureau(s), including antenna colocation requirements of 1.
