Frequency Shift Repeater

The Frequency Shift Repeater (FSR) is designed to solve problems of weak mobile signal, which can expand more coverage than RF repeater and reduce investment for the areas where fiber optic cable is not available.

The whole FSR system consists of two parts: Donor Unit and Remote Unit. They transparently convey and amplify the wireless signal between the BTS (Base Transceiver Station) and mobiles via RF wave at different frequency from the BTS.

The Donor unit receives the BTS signal via a direct coupler closed to the BTS (or via open air RF transmission through the Donor Antenna), then converts it from the working frequency to the link frequency, and transmits the amplified signal to the Remote Unit via the Link Antennas. The Remote Unit will reconvert the signal to the working frequency and provide the signal to the areas where network coverage is inadequate. And the mobile signal is also amplified and retransmitted to the BTS via the opposite direction.

As per the method of receiving BTS signal by the Donor Unit, two types of FSR are available:

• Cable-Access FSR: to receive BTS signal via a direct coupler closed to the BTS (recommended);
• Wireless-Access FSR: to receive BTS signal via a Donor Antenna (applicable when no line of sight can be viewed between the Donor Unit and the Remote Unit as the Donor Unit is installed on the BTS tower).

And both types of FSR can be sorted into 2 sub-categories as per the availability of link frequency:

• In-Band FSR: the link frequency is within the working band of BTS;
• Out-of-Band FSR: the link frequency is out of the working band of BTS.

In comparison with RFR (RF repeater) and FOR (fiber optic repeater), the FSR has the following benefits and disadvantages:

Features

Application

Specifications

Features

• Aluminum-alloy casing has high resistance to dust, water and corroding;
• Best solution to eliminate mutual interference due to sharing the same frequency;
• No stringent isolation requirement for antenna installation;
• Easy to choose installation site;
• RS-232 ports provide links to a notebook for local supervision and to the built-in wireless modem to communicate with the NMS (Network Management System) that can remotely supervise repeater’s working status and download operational parameters to the repeater.

Application Range

To expand signal coverage or fill signal blind area where signal is weak or unavailable.

• Outdoor: Airports, tourism regions, golf courses, tunnels, factories, mining districts, villages, highways…
• Indoor: Hotels, exhibition centers, basements, shopping malls, offices, parking lots, …

The FSR is mainly applicable to such case:

• The area to be covered is far away from the BTS and has no fiber optic connection;
• The distance between the BTS and the area to be covered is 20 km around.

Application Diagram

Application Diagram of Cable-Access Frequency Shift Repeater

Application Diagram of Wireless-Access Frequency Shift Repeater

• GSM (900MHz, 1800MHz, 1900MHz)
• CDMA (450MHz, 800MHz, 1900MHz)

Specifications of GSM Frequency Shift Repeater

		Donor Unit	Remote Unit
Working Frequency (customizable)	Uplink	890~915MHz / 1710~1785MHz / 1895~1910MHz
	Downlink	935~960MHz / 1805~1880MHz / 1975~1990MHz
Link Frequency		Customizable
Transmission Distance		≤ 20km
No. of Channels (for channel shift)		1 / 2
Frequency Error		≤ 0.05ppm
Output Power (customizable)	Uplink	Cable-Access: ≥ 0dBm Wireless-Access: ≥ 30dBm	≥ 33dBm
	Downlink	30~40dBm (1W~10W)	37~43dBm (5W~20W)
Downlink Input Level		Cable-Access: ≥ -10dBm / Wireless-Access: ≥ -70dBm
Gain		Cable-Access: ≥ 45dB Wireless-Access: ≥ 85dB	≥ 90dB
Gain Adjustment Range		1~31dB @ step of 1dB
Voltage Standing Wave Ratio (VSWR)		< 1.3
Noise Figure		< 5dB (only for uplink)
Spurious Emission	Within working band	≤ -15dBm/30kHz
	Out of working band (Δf > 2.5MHz)	9kHz~1GHz: ≤ -36dBm/100kHz 1GHz~12.75GHz: ≤ -30dBm/30kHz
In-Band Intermodulation Attenuation		≤ -40dBc/30kHz
Out-of-Band Suppression	Per band	Δf > 2.5MHz: < -40dBc (downlink); Δf > 10MHz: < -60dBc (uplink)
	Per channel	Δf > 1.98MHz: < -44dBc (downlink); Δf > 1.98MHz: < -38dBc (uplink)
In-Band Ripple		≤ 3dB p-p
System Delay		≤ 10μSec
I/O Impedance		50Ω
RF Connector		N-Type (Female)
Temperature Range		Operation: -25°C ~ +55°C / Storage: -30°C ~ +60°C
Relative Humidity Range		≤ 95% (non condensing)
Power Supply (customizable)		DC +24V / DC -48V / AC 220V±15%, 50Hz / AC 110V±15%, 50Hz
Backup Power Supply (optional)		4 hours
Casing Level		IP65
Dimensions		630mm X 400mm X 230mm	Output power @37~40dBm: 570mm X 325mm X 215mm Output power @40~43dBm: 630mm X 400mm X 230mm
Weight		33kg	Output power @37~40dBm: 27kg Output power @40~43dBm: 35kg
Remote Monitoring/Control via NMS		Supported
ALC (Automatic Level Control)		Supported

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Specifications of CDMA Frequency Shift Repeater

		Donor Unit	Remote Unit
Working Frequency (customizable)	Uplink	450~457.5MHz / 824~849MHz / 1880~1890MHz
	Downlink	460~467.5MHz / 869~894MHz / 1960~1970MHz
Link Frequency		Customizable
Transmission Distance		≤ 20km
No. of Channels (for channel shift)		1 / 2
Frequency Error		≤ 0.05ppm
Output Power (customizable)	Uplink	Cable-Access: ≥ 0dBm Wireless-Access: ≥ 30dBm	≥ 33dBm
	Downlink	30~40dBm (1W~10W)	37~43dBm (5W~20W)
Downlink Input Level		Cable-Access: ≥ -10dBm / Wireless-Access: ≥ -70dBm
Gain		Cable-Access: ≥ 45dB Wireless-Access: ≥ 85dB	≥ 90dB
Gain Adjustment Range		1~31dB @ step of 1dB
Voltage Standing Wave Ratio (VSWR)		< 1.3
Noise Figure		< 5dB (only for uplink)
Spurious Emission	Out of band per channel	Δf ≥750kHz: ≤ -45dBc/30kHz Δf ≥1.98MHz: ≤ -65dBc/30kHz	Δf ≥900kHz: ≤ -42dBc/30kHz Δf ≥1.98MHz: ≤ -59dBc/30kHz
	Within working band	≤ -15dBm/30kHz
	Out of working band (Δf > 2.5MHz)	30MHz~1GHz: ≤ -36dBm/100kHz
In-Band Intermodulation Attenuation		≤ -15dBm/30kHz
Out-of-Band Suppression	Per band	Δf > 2.5MHz: < -40dBc (downlink); Δf > 10MHz: < -60dBc (uplink)
	Per channel	Δf > 1.98MHz: < -44dBc (downlink); Δf > 1.98MHz: < -38dBc (uplink)
In-Band Ripple		≤ 3dB p-p
System Delay		≤ 10μSec
I/O Impedance		50Ω
RF Connector		N-Type (Female)
Temperature Range		Operation: -25°C ~ +55°C / Storage: -30°C ~ +60°C
Relative Humidity Range		≤ 95% (non condensing)
Power Supply (customizable)		DC +24V / DC -48V / AC 220V±15%, 50Hz / AC 110V±15%, 50Hz
Backup Power Supply (optional)		4 hours
Casing Level		IP65
Dimensions		630mm X 400mm X 230mm	Output power @37~40dBm: 570mm X 325mm X 215mm Output power @40~43dBm: 630mm X 400mm X 230mm
Weight		33kg	Output power @37~40dBm: 27kg Output power @40~43dBm: 35kg
Remote Monitoring/Control via NMS		Supported
ALC (Automatic Level Control)		Supported

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