User's Manual

User Manual

2017Cervis, Inc.

2.0 SRF310 Installation

When integrating an SRF310 RTM into a host application, the user must provide all text in the

“FCC Statements” and “Industry Canada Statements” in the host application’s user manual (see

Forward Material). The text must not be modified in any way and presented in a conspicuous

manner that the end user can be reasonably expected to access.

When integrating the SRF310 RTM into host application hardware, the user must properly

connect all the circuits, except _RF_HGM/BPA, identified in Table 1 to suitable host application

signals. The host application firmware must properly control the RTM to ensure that emitted RF

signals comply with all applicable regulatory approvals.

The SRF310 RTM is always used with a provided approved type of antenna, either internal

fixed or external replaceable. If a fixed internal antenna is provided as part of the RTM’s host

application, the host’s on-board coaxial cable connectors are not populated and a direct

connection is made to the internal antenna. If an external antenna is provided as part of the

RTM’s host application, one of the host’s on-board coaxial cable connectors is populated and a

coaxial cable connection is made to the external antenna port. The choice of the particular type

of coaxial connector that is installed will be decided by the designer of the host application. The

internal coaxial cable connector is not accessible to users, so it does not need to be unique.

When provided, external replaceable antennas always have a unique connector such as: RP-

N, RP-SMA, RP-BNC or RP-TNC. A suitable internal coaxial cable jumper with appropriate

connectors must be used to connect the SRF310 RTM host application external antenna port to

the external antenna. The details of a particular host application will influence the design of the

jumper coax, but the external connector must always be of an acceptable unique type.

The coaxial cable used to make the jumper between the RTM and the external antenna

mounting port must be suitable for use in the 902-928 MHz band and have 50 Ohm impedance.

Low loss cable such as RG-316 is suggested, other models of cable may be used provided that

signal loss will be small.

External coaxial cables may be used to help mount a replaceable external antenna in a more

useful location. Such cable must have appropriate unique connectors throughout and must be

made from low loss 50 Ohm coaxial cable. Cables equivalent to LMR-195 are suitable for

lengths up to 30 feet. Longer cables must have suitably lower signal loss, typically using larger

cable such as LMR240, LMR-300, or larger (or equivalent). At some point, a practical limit is

reached where losses in extension cables negate any gains from relocating the antenna.