Icom IC-905 The SHF band challenge, vol 1-4

Vol. 1

― Super High Frequency Band Challenge ―

Dec 10, 2021

Icom Incorporated (Headquarters: Hirano-ku, Osaka, President: Hiroshi Nakaoka) has been

doing technical research on a new project to create a product from scratch by utilizing our

wireless communication technology knowhow cultivated over more than half a century.

Under the theme of “ICOM SHF Project – Super High Frequency Band Challenge –”, we

started to develop a new amateur radio available for use in the 2.4 GHz and 5.6 GHz bands.

Icom engineers are working hard to research and develop a number of never cleared

challenges within the SHF band , such as large cable loss and higher frequency stability

requirements. The ultimate goal is to bring it to the market as a new radio product.

Icom is striving to bring to you a new era in fun and possibilities of an SHF band amateur

radio, which to date has had high technical and equipment hurdles to overcome, and we

hope to make these bands more attractive and active so that anyone can easily operate on

them. We are developing an epoch-making SHF band amateur radio that no one has never

imagined before.

Please watch with intrigue as we continue with our new challenges , such as what kind of

ideas and technologies will be implemented , and what kind of functions and designs will

be used.

― SHF Project ―

Vol. 2

― Super High Frequency Band Challenge ―

Feb 15, 2022

Two Technical Challenges to be Solved

When trying to operate in the SHF band, cable loss will be the biggest bottleneck.

For example, in the 5.6 GHz band, if a 30 meter long, 15 mm diameter high quality coaxial

cable is used to connect between the antenna and transceiver, the cable loss will be 7.2 dB

(at 5.6 GHz) and a 2 watt output from a transceiver will be reduced to 380 mW output from

the antenna.

Another challenge in the SHF band is the ultimate frequency stability requirement.

For example, the IC-9700’s frequency stability is about ±0.5 ppm, but ±0.5 ppm stability in

the 5.6 GHz band means a 2800 Hz deviation. It is completely outside of the IF filter and

cannot be demodulated in the SSB and CW modes. In other words, the practical frequency

stability for SSB and CW mode in the 5.6 GHz band is about ±0.01 ppm or less. This is an

extremely difficult level to achieve with an OCXO (Oven Controlled-crystal Oscillator).

Do Not Use a Long Coaxial Cable

The project team considered several ways to solve the cable loss issue. As a result, we

decided to configure the RF module by directly placing it under the antenna and control it

with a separate controller.

■System Configuration

Install the RF controller

directly under the antenna

and control it with a separate

controller. A LAN cable is

used to connect the controller

to the RF module.

Shack Room

RF module

Controller

Coaxial Cable

LAN cable

A LAN cable is used to connect the controller to the RF module. By using this kind of

cabling set up, only a small length of a coaxial cable (about 30-40 cm) is required between

the RF module and the antenna. Thus, only minimal loss occurs. For example, even if the

controller and RF unit are separated by 30 meters, the loss from coaxial cable is still mini-

mized, due to the short coaxial cable length.

Another Advantage of Using a LAN Cable

When installing the RF module directly under the antenna, the issue of how to supply DC

power arises. Therefore, we decided to adopt PoE (Power over Ethernet) technology that

supplies power over a LAN cable. Since Ethernet twisted pair wiring is limited to 100

meters, it is possible to install the RF module at a location 100 meters away from your

shack (the controller).

By adopting PoE technology, the connection can be made with a single cable,

and the RF module can be installed more freely. Moreover, the PoE technology makes it

possible to supply power with low power loss. Normally, if the power cable is extended to

20 meters, the voltage drop will be too large for a 10 watt transceiver, and it will not oper-

ate properly. With PoE technology, DC power loss can be reduced by raising the voltage

and reducing the current, so it is possible to supply stable power, even if the cable is long.

Ultimate Frequency Accuracy and Stability

Another challenge is frequency accuracy and stability. Even with a high-performance

OCXO, frequency gradually changes due to temperature and aging. The annual deviation

will be ±0.3 ppm and ±1.5 ppm in 10 years. At 5.6 GHz, the deviation will be as much as 8.4

kHz in 10 years. To solve this problem, we have adopted a method that uses a high-preci-

sion 1 Pulse-per-second (1PPS) clock signal from a GNSS (GPS) receiver to enable

advanced frequency management. By synchronizing with this reference signal, the OCXO

frequency can be compensated with high accuracy.

Have Fun with the SHF Band

The SHF band has many challenges, such as cable loss and frequency stability, so there

are high hurdles for developing an SHF band transceiver. By clearing these issues, Icom

will continue to develop further, so that more amateur radio operators can challenge SHF

band operation and discover its enjoyment and potential.

― SHF Project ―

Vol.3

― Super High Frequency Band Challenge ―

April 15, 2022

Design Sketch for <SHF-P1> Concept Model

Releasing the <SHF-P1> Design concept for the Icom SHF Project. This prototype model

will be displayed at the Dayton Hamvention in Ohio, USA from 20th May 2022.

Controller with Compact Size

The controller is designed based on the compact IC-705. The operation system is basically

the same as the IC-705. The Real-time spectrum scope can be adjusted for various band

spans.

■Controller

Front view

Front side (design sketch)

Back view

LAN cable connector

RF Module with 2.4 GHz/5.6 GHz and GPS Antenna Connectors

2.4 GHz and 5.6 GHz antenna connectors enable operation on two SHF bands. In addition

to these connectors, there is also a GPS antenna connector. A high-precision 1 Pulse-per
second (1PPS) clock signal from a built-inGPS receiver enables advanced frequency

management.

■RF Module

Front view

5.6 GHz Antenna connector

2.4 GHz Antenna connector

GPS Antenna connector

Back view

Bottom view

LAN cable connector

― SHF Project ―

Vol. 4

― Super High Frequency Band Challenge ―

June 1, 2022

Debut SHF-P1 Project Concept Model at Dayton Hamvention 2022

On May 20th~22, 2022, one of the world’s largest amateur radio events, “Hamvention 2022”

was held at the Greene County Fairgrounds and Expo Center in Xenia, Ohio. In 2020 and

2021, it was cancelled due to Covid-19, and so it was the first time to be held in three years.

Enthusiastic amateur radio operators made a long queue to wait for admission. We had high

expectations of this event that was held after such a long while.

Just after the doors opened, the ICOM booth got very crowded with many amateur radio

operators. The SHF-P1 concept project model got a lot of attention, from all the booth

visitors. Various questions about the SHF-P1 project were asked regarding pricing, the

timing of release, the frequency coverage, and other specifications. We learned that there

is a high interest in the SHF-P1 project.

Future schedule

The SHF-P1 Project concept model will be displayed at following events

From 24 June 2022: HAM RADIO in Friedrichshafen Germany

― SHF Project ―